KYIV, Ukraine (NewsNation) — Russian forces pressed their assault on Ukrainian cities Friday, with new missile strikes and shelling on the capital Kyiv and the outskirts of the western city of Lviv, as world leaders pushed for an investigation of the Kremlin’s repeated attacks on civilian targets.

There were numerous reports of an attack on or near the airport serving Lviv, a city near the Polish border. That area has been relatively violence-free since the start of the conflict three weeks earlier, though one missile strike nearby did kill 35 people.

Multiple blasts hit in quick succession shaking nearby buildings, witnesses said. The missiles were launched from the Black Sea, but the Ukrainian air force’s western command said it had shot down two of six missiles in the volley. A bus repair facility was also damaged, Lviv’s Mayor Andriy Sadovyi said.

The attack on the outskirts of Lviv was the closest strike yet to the center of the city, which has become a crossroads for people fleeing from other parts of Ukraine and for others entering to deliver aid or fight.

In the Podil neighborhood of Kyiv, early morning barrages also hit a residential building killing at least one person, according to emergency services, who said 98 people were evacuated from the building. Kyiv Mayor Vitali Klitschko said 19 were wounded in the shelling.

Two others were killed when strikes hit residential and administrative buildings in the eastern city of Kramatorsk, according to Pavlo Kyrylenko, the regional governor.

Rescue workers continued to search for survivors Friday 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.

Lyudmyla Denisova, Ukrainian human rights ombudswoman, said Friday that 130 people had been rescued so far from the rubble of the theatre hit by an airstrike.

In a televised address, Denisova said rescue work was ongoing at the site, where many people were sheltering underground before the building was hit.

Hundreds of civilians had been taking shelter in the grand, columned theater in central Mariupol after their homes were destroyed in three weeks of fighting in the southern port city of 430,000.

More than a day after the airstrike, there were no reports of deaths.

Russia’s military denied bombing the theater or anyplace else in Mariupol on Wednesday.

The strike against the theater was part of a furious bombardment of civilian sites in multiple cities over the past few days.

In the northern city of Chernihiv, at least 53 people, including an American, had been brought to morgues over the past 24 hours, killed amid heavy Russian air attacks and ground fire, the local governor, Viacheslav Chaus, told Ukrainian TV on Thursday.

Jim Hill, an Idaho native, was staying in the city to get medical care for his partner who is a Ukrainian citizen. His sister said on social media that he died while waiting in line for bread.

As the conflict in Ukraine entered its fourth week, about 3.3 million have fled abroad, per United Nations data, in what has become Europe’s fastest-growing refugee crisis since World War II.

More than 2 million refugees have entered Poland since the Russian invasion started, the Polish border guard said Friday.

Ukrainian President Volodymyr Zelenskyy called for more help for his country in a video address to German lawmakers, saying thousands of people have been killed, including 108 children. He also referred to the dire situation in Mariupol, saying: “Everything is a target” for Russian forces.

The address began with a delay because of a technical problem caused by an attack close to where Zelenskyy was speaking, Bundestag deputy speaker Katrin Goering-Eckardt said.

On Friday, a spokesman for Olaf Scholz says the German chancellor spoke by phone with Russian President Vladimir Putin and urged him to agree to an immediate cease-fire in Ukraine.

During the hour-long call, Scholz also called for an improvement to the humanitarian situation and progress in efforts to find a diplomatic solution to the conflict.

Poland’s Prime Minister Mateusz Morawiecki said he will formally submit a proposal for a peacekeeping and humanitarian mission on Ukraine’s territory at next week’s extraordinary NATO summit.

Morawiecki stressed that Poland had already made the proposal during a meeting of NATO defense ministers in Brussels on Wednesday. Denmark has expressed readiness to join such a mission.

NATO leaders have been opposed to the alliance’s presence in Ukraine over concerns it could escalate the conflict.

On Friday, the head of the Russian delegation in talks with Ukrainian officials said both sides narrowed their differences on the issue of Ukraine dropping its bid to join NATO and adopting a neutral status. He added that the sides are now “halfway” on issues regarding the demilitarization of Ukraine. 

President Joe Biden is set to attend the NATO summit in Brussels on Thursday that will focus on Russia’s invasion of Ukraine and European security.

He and China’s Xi Jinping spoke for nearly two hours on Friday. China’s Foreign Ministry was the first to issue a readout of the video conversation, deploring “conflict and confrontation” as “not in anyone’s interest,” without assigning any blame to Russia.

U.S. Secretary of State Antony Blinken said American officials are evaluating and documenting potential war crimes committed by Russia in Ukraine. Blinken said the intentional targeting of civilians is a war crime, for which there will be “massive consequences.”