Ukrainian refugees from the Azovstal steel plant in Mariupol are seen in a bus as they arrive at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich TPX IMAGES OF THE DAY 

Ukrainian refugee Alisa, 4, from the Azovstal steel plant in Mariupol, whose mother was detained by Russian servicemen during the evacuation, is seen as she arrives at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich 

A Ukrainian police officer guards as refugees from the Azovstal steel plant in Mariupol arrive at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich TPX IMAGES OF THE DAY 

Ukrainian refugees from the Azovstal steel plant in Mariupol arrive at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich 

Ukrainian refugees from the Azovstal steel plant in Mariupol are seen in a bus as they arrive at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich 

A Ukrainian refugee from the Azovstal steel plant in Mariupol arrives at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich 

Ukrainian refugees from the Azovstal steel plant in Mariupol are seen in a bus as they arrive at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich 

A Ukrainian refugee from Azovstal steel plant in Mariupol is seen in a bus as she arrives at a registration and humanitarian aid centre for internally displaced people, amid Russia's ongoing invasion of Ukraine, in Zaporizhzhia, Ukraine May 8, 2022. REUTERS/Gleb Garanich 

A view shows an explosion at a plant of Azovstal Iron and Steel Works during Ukraine-Russia conflict in the southern port city of Mariupol, Ukraine May 8, 2022. REUTERS/Alexander Ermochenko 

A young woman evacuated from Azovstal steel plant in Mariupol is seen at a temporary accommodation centre in the village of Bezimenne, during Ukraine-Russia conflict in the Donetsk Region, Ukraine May 6, 2022. REUTERS/Alexander Ermochenko 

A young woman evacuated from Azovstal steel plant in Mariupol leans over her dog at a temporary accommodation centre in the village of Bezimenne, during Ukraine-Russia conflict in the Donetsk Region, Ukraine May 6, 2022. REUTERS/Alexander Ermochenko