Kyiv - Ukrainian authorities struggled to determine the fate of hundreds of civilians who had been sheltering in a theater smashed by a Russian airstrike in the besieged city of Mariupol as officials said Russian artillery Thursday destroyed more civilian buildings in another frontline city.

A photo released by Mariupol’s city council showed an entire section of the large, 3-story theater had collapsed after the strike Wednesday evening. Several hundred people had taken refuge in the building, seeking safety amid Russia’s 3-week, strangulating siege of the strategic Azov Sea port city.

A view shows Donetsk Regional Theatre of Drama destroyed by an airstrike/ REUTERS

Rubble had buried the entrance to the shelter inside the theater, and it was not yet known how many people were killed or injured, Pavlo Kyrylenko, head of the Donetsk regional administration, said on Telegram.

Russian airstrikes also hit a municipal swimming pool complex in Mariupol where civilians, including women and children, had been sheltering, Kyrylenko said. “Now there are pregnant women and women with children under the rubble there,” he wrote, though the number of casualties was not immediately known.

The Russian defense ministry denied bombing the theater or anywhere else in Mariupol on Wednesday.

On Thursday, Russian artillery destroyed a school and a community center in Merefa, a city near the northeast city of Kharkiv, according to Merefa’s mayor Veniamin Sitov. There were no known civilian casualties. The Kharkiv region has seen heavy bombardment as stalled Russian forces try to advance in the area.

A fire broke out in a Kyiv apartment building early Thursday after it was hit by the remnants of a downed Russian rocket, killing one person and injuring at least three others, according to emergency services. Firefighters evacuated 30 people from the top floors of the 16-story building and extinguished the blaze within an hour.

Russian Foreign Minister Sergey Lavrov said after Tuesday’s meeting that a neutral military status for Ukraine was being “seriously discussed” by the two sides, while Zelenskyy said Russia’s demands for ending the war were becoming “more realistic.”

Wednesday’s talks, held by video, appeared to wade more deeply into technicalities. Although both sides have pointed to limited progress in peace talks this week, President Vladimir Putin, who ordered Russia's invasion on Feb. 24, showed little sign of relenting.

Russia has demanded that NATO pledge never to admit Ukraine to the alliance or station forces there.

Zelensky addresses US congress
Earlier Wednesday, Zelenskyy went before the U.S. Congress via video and, invoking Pearl Harbor and 9/11, pleaded with America for more weapons and tougher sanctions against Russia, saying: “We need you right now.”

Speaker of the House Nancy Pelosi, D-Calif., introduces Ukrainian President Volodymyr Zelenskyy to speak to the U.S. Congress by video /AP Photo

President Joe Biden announced the U.S. was sending an additional $800 million in military aid to Ukraine. He also called Putin a “war criminal,” in his sharpest condemnation since the invasion began.

The fighting has led more than 3 million people to flee Ukraine, the U.N. estimates. The death toll remains unknown, though Ukraine has said thousands of civilians have died.

Putin a “war criminal”, Biden
US President Joe Biden has labelled Russian leader Vladimir Putin a "war criminal" in a move likely to escalate diplomatic tensions even further.

It is the first time Biden has used such language to condemn President Putin while responding to a reporter's question at the White House. The White House later said he was "speaking from his heart" after seeing "barbaric" images of the violence in Ukraine, rather than making any official declaration.

President Vladimir Putin, in a offensive televised speech spoke harshly against "traitors" at home who helped the West, said the Russian people would throw them out.

Kyiv and its Western allies believe Russia launched the unprovoked war to subjugate a neighbour that Putin calls an artificial state carved out of Russia. Moscow says it is carrying out a "special operation" to disarm it and "denazify".

Heavily outnumbered Ukrainian forces have prevented Moscow from capturing any of Ukraine's biggest cities so far despite the largest assault on a European state since World War Two. More than 3 million Ukrainians have fled and thousands of civilians and combatants have died.
-AP/BBC/Reuters