Rescuers search theater rubble as Russian attacks continue

This photo released by Donetsk Regional Civil-Military Administration Council on Wednesday shows the Drama Theatre, damaged after shelling, in Mariupol, Ukraine. (Donetsk Regional Civil-Military Administration Council/via AP)

People put up plastic sheets to cover the broken windows of their apartments after parts of a Russian missile, shot down by Ukrainian air defense, landed on an apartment block, according to authorities, in Kyiv, Ukraine, Thursday, March 17, 2022. Russian forces destroyed a theater in Mariupol where hundreds of people were sheltering Wednesday and rained fire on other cities, Ukrainian authorities said, even as the two sides projected optimism over efforts to negotiate an end to the fighting. (AP Photo/Vadim Ghirda)

People clear debris outside a medical center damaged after parts of a Russian missile, shot down by Ukrainian air defense, landed on a nearby apartment block, according to authorities, in Kyiv, Ukraine, Thursday, March 17, 2022. Russian forces destroyed a theater in Mariupol where hundreds of people were sheltering Wednesday and rained fire on other cities, Ukrainian authorities said, even as the two sides projected optimism over efforts to negotiate an end to the fighting. (AP Photo/Vadim Ghirda)

Medical staff sit in a hospital basement, used as a bomb shelter, during an air raid alarm in Brovary, north of Kyiv, Ukraine, Thursday, March 17, 2022. (AP Photo/Felipe Dana)

Ukrainian firefighters extinguish a blaze at a warehouse after a bombing in Kyiv, Ukraine, Thursday, March 17, 2022. Russian forces destroyed a theater in Mariupol where hundreds of people were sheltering Wednesday and rained fire on other cities, Ukrainian authorities said, even as the two sides projected optimism over efforts to negotiate an end to the fighting. (AP Photo/Vadim Ghirda)

Ukrainian servicemen carry containers backdropped by a blaze at a warehouse after a bombing on the outskirts of Kyiv, Ukraine, Thursday, March 17, 2022. Russian forces destroyed a theater in Mariupol where hundreds of people were sheltering Wednesday and rained fire on other cities, Ukrainian authorities said, even as the two sides projected optimism over efforts to negotiate an end to the fighting. (AP Photo/Vadim Ghirda)

People who fled the war in Ukraine wait at the train station in Przemysl, southeastern Poland, Thursday, March 17, 2022. Poland has admitted some 1.95 million refugees fleeing war and Russian aggression on Ukraine. (AP Photo/Petros Giannakouris)

This image made available by Azov Battalion, shows the drama theater, damaged after shelling, in Mariupol, Ukraine, Thursday March 17, 2022. Rescuers are searching for survivors in the ruins of a theater ripped apart by Russian airstrikes in the besieged city of Mariupol, while ferocious Russian bombardment killed dozens in a northern city over the past day, according to the local governor. (Azov Battalion via AP)

This satellite image provided by Maxar Technologies shows the Mariupol Drama Theater in Mariupol, Ukraine on Monday, March 14, 2022. Ukrainian officials say Russian forces destroyed the theater in the city of Mariupol where hundreds of people were sheltering. There was no immediate word on deaths or injuries in what the Mariupol city council said was an airstrike on the theater Wednesday. The Maxar satellite imagery firm said images from Monday showed the word “children” had been written in large white letters in Russian in front of and behind the building. (Maxar Technologies via AP)

KYIV, Ukraine — Rescue workers searched for survivors Thursday in the ruins of a theater blown apart by a Russian airstrike in the besieged city of Mariupol, while scores of Ukrainians across the country were killed in ferocious urban attacks on a school, a hostel and other sites.