A pallbearer wearing a gas mask as a preventive measure against the coronavirus disease (COVID-19) put flowers on the grave of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) participate in a burial of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) participate in a burial of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) participate in a burial of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) while carrying a coffin holding the body of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) while carrying a coffin holding the body of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) while carrying a coffin holding the body of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

Pallbearers wear gas masks to protect themselves from the coronavirus disease (COVID-19) while carrying a coffin holding the body of a man who died of a heart attack, unrelated to the coronavirus disease, at a cemetery in La Paz, Bolivia March 23, 2020. Picture taken March 23, 2020. REUTERS/David Mercado

A demonstrator attacks a riot police vehicle amidst tear gas during a protest against Chile's government in Santiago, Chile November 1, 2019. REUTERS/Jorge Silva TPX IMAGES OF THE DAY

Demonstrators react as riot police fire tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

A demonstrator is seen amidst smoke from tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

A reporter reacts after being hit by tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

Demonstrators are seen amidst smoke from tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Edgar Su

Police officers fire tear gas at demonstrators during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu TPX IMAGES OF THE DAY

Demonstrators are seen amidst smoke from tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Edgar Su

Police officers fire tear gas at demonstrators during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

A lawmaker Roy Kwong reacts after the tear gas and pepper spray was used by a police during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Edgar Su

A demonstrator reacts to a tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

Police officers fire tear gas and use pepper spray at the demonstrators during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

Police officers fire a tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

A demonstrator is seen amidst smoke from tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu TPX IMAGES OF THE DAY

A police officer fires a tear gas at the demonstrators during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

A lawmaker Roy Kwong reacts after the tear gas and pepper spray was used by a police during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Edgar Su

Police officers fire a tear gas at the demonstrators during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Edgar Su

Police officers fire a tear gas at the demonstrators during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Edgar Su

A demonstrator reacts to a tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

Demonstrators react to a tear gas during a protest against the Yuen Long attacks in Yuen Long, New Territories, Hong Kong, China July 27, 2019. REUTERS/Tyrone Siu

Venezuelan migrant Teresa Amaro, 83, from Barquisimeto, poses for a picture with her daughter Maite Perez, 43, and her grandson Edwar Coste, 7, while they rest at the Ecuadorian-Peruvian border service centre before they continue their journey into Peru, on the outskirts of Tumbes, Peru, June 15, 2019. Amaro, who had previously suffered a heart attack, said: "It is tough to find medicines, and when you find them they are very expensive, and there is not enough money to buy them. We didn't have electricity. We didn't have cooking gas and we were cooking with firewood. By the time we left, we already had a month without gas in the whole area, and we couldn't find firewood either. I did not want to come, but they told me: 'Mama, we're not going to leave you alone.'" REUTERS/Carlos Garcia Rawlins SEARCH "MOTHERS REFUGEE" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

Former President Manuel Zelaya is helped by aides while being overcome by tear gas during a protest against the re-election of Honduras' President Juan Orlando Hernandez in Tegucigalpa, Honduras January 12, 2018. Reuters photographer Jorge Cabrera: "I was covering a protest against Honduran President Juan Orlando Hernandez in the capital Tegucigalpa when things turned violent. Some protesters vandalized the front of the Marriott Hotel, and police responded with tear gas and warning shots. Among the protesters was former president Manuel Zelaya. Zelaya tried to quell the clashes but got caught in the middle of the scuffle and his hat fell on the ground. As he tried to retrieve it, Zelaya was gassed and attacked by police. The photo I took captured his bodyguards as they tried to get him to safety while Zelaya catches his breath, holding a gas mask. What struck me the most was how the former president seemed to ignore the danger - the teargas and bullets - and he appeared solely focused on getting his hat back. But police soon charged again, and Zelaya never managed to retrieve it." REUTERS/Jorge Cabrera SEARCH "POY STORY" FOR THIS STORY. SEARCH "REUTERS POY" FOR ALL BEST OF 2018 PACKAGES. TPX IMAGES OF THE DAY.

Tear gas canisters are fired by Israeli troops at Palestinian demonstrators during clashes at a protest demanding the right to return to their homeland, at the Israel-Gaza border in the southern Gaza Strip, April 27, 2018. REUTERS/Ibraheem Abu Mustafa TPX IMAGES OF THE DAY

Tear gas canisters are fired by Israeli troops at Palestinian demonstrators during clashes at a protest demanding the right to return to their homeland, at the Israel-Gaza border in the southern Gaza Strip, April 27, 2018. REUTERS/Ibraheem Abu Mustafa TPX IMAGES OF THE DAY

Limar and Masa al-Qari, child survivors of the suspected poison gas attack, walk outside a tent for the displaced, in the Northern Aleppo countryside, Syria April 17, 2018. Picture taken April 17, 2018. REUTERS/Mahmoud Hassano TPX IMAGES OF THE DAY

Limar al-Qari, a child survivor of the suspected poison gas attack, is seen inside a tent for the displaced, in Northern Aleppo countryside, Syria April 17, 2018. Picture taken April 17, 2018. REUTERS/Mahmoud Hassano

Limar and Masa al-Qari, child survivors of the suspected poison gas attack, walk outside a tent for the displaced, in the Northern Aleppo countryside, Syria April 17, 2018. Picture taken April 17, 2018. REUTERS/Mahmoud Hassano

Limar and Masa al-Qari, child survivors of the suspected poison gas attack, hold hands outside a tent for the displaced, in the Northern Aleppo countryside, Syria April 17, 2018. Picture taken April 17, 2018. REUTERS/Mahmoud Hassano

Rasha Edlibi, a survivor of the suspected poison gas attack, sits with her two daughters inside a tent for the displaced, in the Northern Aleppo countryside, Syria April 17, 2018. Picture taken April 17, 2018. REUTERS/Mahmoud Hassano

Rasha Edlibi, a survivor of the suspected poison gas attack, sits with her two daughters inside a tent for the displaced, in the Northern Aleppo countryside, Syria April 17, 2018. Picture taken April 17, 2018. REUTERS/Mahmoud Hassano

Diplomatic measures announced against Russia by the United States, Canada, Australia, several EU countries and Ukraine in response to the poisoning of a former Russian double agent with military-grade nerve agent in the English town of Salisbury.

Maps locating areas cordoned off by police after the nerve gas attack in England on a Russian former spy

A man inspects damage at a gas station after air strikes in the city of Saada, Yemen January 6, 2018. REUTERS/Naif Rahma

I went to the road just outside Ramallah, as on previous days, because that is one of the places in the West Bank where Palestinians have been protesting against U.S. President Donald Trump's recognition of Jerusalem as Israel's capital. The 100-metre stretch leads from the city limits of Ramallah to the Jewish settlement of Beit El, and has a filling station and a traffic circle. Earlier on Friday, which Palestinians were calling a "Day of Rage", I had tried the Kalandia crossing point into the West Bank, but the Israelis had thrown tear gas and I knew this would make taking good photographs difficult. Outside Beit El, a group of paramilitary Israeli police had driven back hundreds of Palestinians who were throwing rocks and burning tyres. I was photographing the protesters, and did not see another Palestinian who apparently emerged close to the Israeli squad from a hiding place near the traffic circle. I heard the Israeli police shooting, and turned around. On instinct, I started taking pictures, all the time trying to keep well out of the line of fire. When the Palestinian fell, I could see that he was holding a knife, and wearing what looked like a suicide bomb vest. Israeli police said he had managed to stab and wound one of their number before being shot. Palestinian medics later said the attacker was dead, and that his bomb belt had been fake. REUTERS/Goran Tomasevic/File photo SEARCH "TOMASEVIC SHOT" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. Matching text: ISRAEL-PALESTINIANS/SHOOTING

Demonstrators, who broke into a hotel and attacked women attending an election meeting, run through tear gas thrown by riot policemen in Kisumu, Kenya September 13, 2017. REUTERS/James Keyi

Demonstrators, who broke into a hotel and attacked women attending an election meeting, run through tear gas thrown by riot policemen in Kisumu, Kenya September 13, 2017. REUTERS/James Keyi

A protester raises his umbrellas after riot police fire tear gas to disperse protesters in Hong Kong, September 28, 2014.ÊLarge-scale protests calling for a fully democratic vote to choose Hong Kong's next leader rocked the city for over two months in 2014. The so-called Occupy Central campaign was the most serious challenge to China's authority since the 1989 pro-democracy demonstrations and crackdown in Beijing's Tiananmen Square. Umbrellas became a symbol of the 2014 campaign as protesters used them to fend off police pepper spray attacks. REUTERS/Tyrone Siu/File photo SEARCH "HONGKONG TIMELINE" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

A Kashmiri demonstrator kicks a tear gas canister thrown by the Indian police during a protest near the site of an attack on an Indian army base by suspected separatist militants in Panzgam in Kashmir's Kupwara district, April 27, 2017. REUTERS/Danish Ismail

Main chemical warfare agents

China's U.N. Ambassador Liu Jieyi speaks to media as he departs following U.N. Security Council consultations regarding a deadly gas attack in Syria at U.N. headquarters in New York, U.S., April 6, 2017. REUTERS/Lucas Jackson

Deputy Russian U.N. Ambassador Vladimir Safronkov departs after U.N. Security Council consultations regarding a deadly gas attack in Syria at U.N. headquarters in New York, U.S., April 6, 2017. REUTERS/Lucas Jackson

Deputy Russian U.N. Ambassador Vladimir Safronkov departs after U.N. Security Council consultations regarding a deadly gas attack in Syria at U.N. headquarters in New York, U.S., April 6, 2017. REUTERS/Lucas Jackson

Deputy Russian U.N. Ambassador Vladimir Safronkov departs after U.N. Security Council consultations regarding a deadly gas attack in Syria at U.N. headquarters in New York, U.S., April 6, 2017. REUTERS/Lucas Jackson

U.S. Ambassador to the United Nations, Nikki Haley, departs after U.N. Security Council consultations regarding a deadly gas attack in Syria at U.N. headquarters in New York, U.S., April 6, 2017. REUTERS/Lucas Jackson

U.S. Ambassador to the United Nations, Nikki Haley, departs after U.N. Security Council consultations regarding a deadly gas attack in Syria at U.N. headquarters in New York, U.S., April 6, 2017. REUTERS/Lucas Jackson