(CN) — After three weeks of war in Ukraine, talks to end the fighting intensified on Wednesday even as Ukrainian President Volodymyr Zelenskyy appealed to the U.S. Congress to intervene to stop Russia's invasion and a bomb was dropped on a theater where hundreds of civilians were sheltering.
Wednesday’s hope for peace talks were overshadowed by more reports of overnight shelling of towns and cities, intense firefights, Ukrainian counterattacks and more civilian deaths.
By Wednesday evening, Russia was accused of what could be its most brutal attack on civilians yet after a Russian warplane allegedly dropped a bomb on a large theater in the center of the besieged southern port city of Mariupol. Images showed the building turned to rubble. Mariupol’s city officials estimated that more than 1,000 people were sheltering in the Drama Theater. It remained unclear late Wednesday how many people may have been killed.
Mariupol is the scene of horrific fighting and a catastrophic humanitarian disaster with hundreds of thousands of people lacking adequate electricity, water, food and medical supplies. Ukraine has said more than 2,500 people have been killed in the city since Russia launched its invasion on Feb. 24. Hardcore Ukrainian fighters affiliated with the ultra-nationalistic far-right Azov Regiment are fighting Russian forces there and the battle has moved closer to the city center, according to military sources.
Elsewhere, Ukraine reported that at least 10 civilians waiting in line for bread in Chernihiv were killed by Russian shelling on Wednesday morning. Chernihiv, a medium-sized city north of the capital Kyiv, has been the site of horrific fighting for more than two weeks. The city lies on the path Russian troops have taken from Belarus to attack Kyiv.
Russia’s Ministry of Defense denied any responsibility for the attack on the Mariupol theater and instead accused Azov soldiers of blowing it up, according to RIA Novosti, the Russian state news agency. Russia also denied attacking civilians in Chernihiv. Throughout the war, Russia has consistently denied attacking civilians and blamed instead Ukrainian forces of seeking to cause “provocations” by bombing up civilian buildings, attacking from residential buildings and using civilians as “human shields.”
With so much horror and death in this fratricidal war, the hope is that both sides can end the fighting in the coming days by agreeing to a ceasefire and a peace deal.
This week, Zelenskyy's government resumed ceasefire talks with Russia and as a major concession Kyiv is considering agreeing to not join NATO in exchange for a withdrawal of Russian troops.

Mykhailo Podoliak, one of Zelenskyy’s top advisers, told PBS that the two sides were working to get Russian President Vladimir Putin and Zelenskyy to meet in the coming days, Ukrinform, a Ukrainian state news agency reported.
“The only option to end this war is direct talks between the two presidents, and that is what we are working on with these peace talks. We are working on documents that the presidents will be able to discuss further and sign,” he said. He added that he thought a ceasefire could be called soon.
The Financial Times reported that negotiators had drawn up a tentative 15-point plan to end the war. Ukraine renouncing NATO membership is a cornerstone to the deal.
Under the proposals, Ukraine also would accept limits on its armed forces, promise not to allow foreign military bases or weaponry on its territory but get security protection from its allies, such as the United States, the United Kingdom and Turkey, the Financial Times reported, citing three people involved in the talks.