A Brazilian soldier strip searches youths during a patrol near Alemao slums complex in Rio de Janeiro, August 22. Brazil launched a sweeping operation this week targeting warring drug gangs in slums across Rio de Janeiro.

REUTERS/Ricardo Moraes 

Army members mourn during the burial of Brazilian soldier Marcus Vinicius Viana Ribeiro, who was shot dead during an operation against drug gangs in Alemao slum complex, in Rio de Janeiro, August 23, 2018. Ribeiro, and two other soldiers, are the first troops to die in the six-month-old federal intervention in Rio, which has been criticized for military tactics, a lack of transparency and unclear goals.

REUTERS/Pilar Olivares 

Brazilian soldiers patrol in the Chatuba slum in Rio de Janeiro, August 23. REUTERS/Pilar Olivares 

Suspects are arrested after violent clashes with Brazilian Army soldiers after taking a family hostage in Alemao slums complex in Rio de Janeiro, August 20. REUTERS/Ricardo Moraes 

Brazilian soldiers and Civil policemen carry drugs seized on the woods of Chatuba slum during an operation against drug dealers in Rio de Janeiro, August 22. REUTERS/Ricardo Moraes 

Brazilian soldiers patrol in the Complexo da Penha slum in Rio de Janeiro, August 23. REUTERS/Pilar Olivares 

Brazilian soldiers react as they leave the burial of Soldier Joao Viktor da Silva, who was shot dead during an operation against drug gangs in Alemao slums complex, in Japeri, near Rio de Janeiro, August 21. REUTERS/Ricardo Moraes 

Relatives of Brazilian soldier Marcus Vinicius Viana Ribeiro, who was shot dead during an operation against drug gangs in Alemao slum complex, mourn during his burial in Rio de Janeiro, August 23. REUTERS/Pilar Olivares 

A Brazilian Army soldier patrols during an operation against drug gangs in Alemao slums complex in Rio de Janeiro, August 21. REUTERS/Pilar Olivares 

Drugs and guns seized from suspects arrested after they took a family hostage during violent clashes with Brazilian Army soldiers in Alemao slums complex, in Rio de Janeiro, August 20. REUTERS/Ricardo Moraes 

A Brazilian soldier patrols in the Complexo da Penha slum in Rio de Janeiro, August 23. REUTERS/Pilar Olivares 

Brazilian Army soldiers patrol, near grazing horses, during an operation against drug gangs in Alemao slums complex in Rio de Janeiro, August 20. REUTERS/Ricardo Moraes 

A Brazilian soldier patrols in Chatuba slum during an operation against drug dealers in Rio de Janeiro, August 22. REUTERS/Ricardo Moraes 

Brazilian Army soldiers take cover during a shootout with drug gangs during an operation in Alemao slums complex in Rio de Janeiro, August 20. REUTERS/Ricardo Moraes 

A Brazilian soldier patrols the Alemao complex slum during an operation against drug dealers in Rio de Janeiro, August 21. REUTERS/Ricardo Moraes