A Russian military strike hit an evacuation crossing point in a Kyiv suburb Sunday, killing a family with two children and several other civilians trying to flee the Russian invasion, according to the city’s mayor, as civilian casualties seeking safety from the onslaught continue to rise. Two mortar or artillery shells hit the checkpoint in the suburb of Irpin, northwest of Kyiv, Ukrainian authorities said, which has been the site of intense shelling by the Russian military in recent days. Irpin Mayor Oleksandr Markushyn said eight civilians have been killed across the district, and international media filming at the checkpoint reported that a shell landed as a stream of civilians was coming through. “A family died,” Markushyn said in a statement. “In front of my eyes, two small children and two adults died.” Video from the moment the strike killed a family shows a Ukrainian soldier standing outside a building on a street. Suddenly, an explosion is seen and heard on the video. Debris is heard raining down on the building and the street is obscured by a dust cloud. A number of journalists are heard reacting to the strike. As the scene begins clearing, someone is seen pulling the Ukrainian soldier away. Other soldiers run across the street and appear to be checking the condition of a number of individuals on the ground. “Medic,” someone is heard repeatedly screaming. Photographs from the Associated Press showed bodies on the ground covered by sheets, with suitcases standing upright nearby. CNN has determined the civilians were killed in the Russian military strike seen in the video. The Kyiv Regional Military Administration appealed to international organizations for help in resolving a growing humanitarian crisis. “Thousands of people found themselves in isolation, because of direct hostilities, and in some places for 5-6 days they survive without electricity, water, food, medical help and means of subsistence. They are in direct danger,” it said. The Office of the UN High Commissioner for Human Rights said Sunday that more than 360 civilians had been killed in Ukraine since Russia’s invasion began, while acknowledging that the real figure is likely “considerably higher.” CNN cannot independently verify the casualty numbers. The UN also reports more than 1.5 million refugees have fled Ukraine since February 24. Evacuation corridors closed In the country’s southeast, hopes that a second attempt to open up safe evacuation routes for civilians in Mariupol and Volnovakha might succeed – after a first effort failed on Saturday – were dashed within hours. The governor of the Donetsk region, Pavlo Kyrylenko, said on Facebook on Sunday that the planned “evacuation convoy with local residents was never able to leave Mariupol today: the Russians began to regroup their forces and heavy shelling of the city. It is extremely dangerous to evacuate people in such conditions.” Kyrylenko added that a convoy carrying humanitarian aid from the central city of Zaporizhzhia, three hours from Mariupol, “has not yet reached its destination and is currently on its way.” The International Committee of the Red Cross (ICRC) also said Sunday’s planned evacuation in Mariupol had failed. “Today, our team began opening up the evacuation route from Mariupol before hostilities resumed. We remain in Mariupol and are ready to help facilitate further attempts – if the parties reach an agreement, which is for them alone to implement and respect,” the ICRC said on Twitter. “People in Mariupol and in other places across #Ukraine are living in desperate situations. They must be protected at all times. They are not a target. People urgently need water, food, shelter. The basics of life. We need safety guarantees to be able to bring them aid.” Ukrainian lawmaker Inna Sovsun claimed Sunday that Russian forces had damaged a gas pipeline in southeastern Ukraine, leaving hundreds of thousands of people without heat in bitter temperatures. “Donetsk-Mariupol gas pipeline was damaged by #Russian occupants. Now, more than 750,000 of people are left without any heat, while it’s still often below 0°C (32 degrees Fahrenheit) outside,” Sovsun said on Twitter. Separately, television and radio broadcasts have been knocked out in Ukraine’s second largest city, Kharkiv, after Russian military strikes, according to the Regional Administration. In a post on Facebook Sunday, the Regional Administration said “repeated shelling” of the TV tower in Kharkiv had knocked out broadcasting capabilities. Russia has fired a total of 600 missiles since the invasion of Ukraine began, a senior US defense official told CNN on Sunday, and has committed approximately 95% of its amassed combat power inside Ukraine. Earlier Sunday, heavy shelling was reported to the west and northwest of Kyiv. The impact of explosions was heard by CNN teams in Kyiv and in rural areas to the southwest. “They (Russian troops) captured Hostomel and Bucha yesterday (Saturday). The Russians entered there,” said Oleksiy Arestovych, an adviser in the Ukrainian President’s Office, referring to two suburbs northwest of Kyiv. “They have injured many children and do not allow to evacuate them, despite numerous appeals at the highest state level to provide a ‘green corridor’ from Bucha and Irpin. There are many children in the basements.” Arestovych described the situation as a “catastrophe,” adding that discussions were going on “at the highest level with international humanitarian institutions, through mediators with the Russians” in order to find a way out for those who are trapped. Several children have died, according to Ukraine’s Ministry of Health. Separately, Ukrainian President Volodymyr Zelensky warned Sunday that Russia was preparing to bomb the Black Sea port city of Odessa in southern Ukraine and said the airport in Vynnytsia, in the west of the country, had been destroyed by a rocket strike. In an address broadcast on Facebook, Zelensky said: “Russian people always used to come to Odessa and they only knew warmth and generosity and what’s now? Artillery, bombs against Odessa. This will be a war crime. This will be (a) historic crime.” In a separate message, Zelensky again appealed for a no-fly zone to be imposed over Ukraine, following the destruction of Vynnytsia’s airport. “They continue to ruin our infrastructure our life, which we have built, and our parents, and grandparents, many generations of Ukrainians. We repeat every day – close the skies over Ukraine,” he added. US and European officials have been discussing how the West would support a government in exile helmed by Zelensky should he have to flee Kyiv, Western officials told CNN. The discussions have ranged from supporting Zelensky and top Ukrainian officials in a potential move to Lviv in western Ukraine, to the possibility that Zelensky and his aides are forced to flee Ukraine altogether and establish a new government in Poland, the officials said. Western officials have been wary of discussing a government in exile directly with Zelensky because he wants to stay in Kyiv and has so far rejected conversations that focus on anything other than boosting Ukraine in its fight against Russia, two Western diplomats said. Calls for more support As the Russian invasion continues, Zelensky has reiterated his pleas for US and NATO assistance in establishing a no-fly zone over Ukraine – a move which could prevent Russian forces from carrying out airstrikes against the country. But there are fears such a move could be seen as an escalation, with Russian President Vladimir Putin warning on Saturday he would consider countries imposing a no-fly zone over Ukraine as “participants in a military conflict.” Zelensky has repeatedly asked NATO and Western officials to impose a no-fly zone over Ukraine, but both say they oppose such a move. In an impassioned call to US lawmakers Saturday, Zelensky also encouraged Eastern European nations to provide Ukraine with fighter jets, stressing they were needed to defend against Russian aggression. On the call, Zelensky said if the West won’t impose a no-fly zone they should give Ukraine planes. A White House spokesperson confirmed the United States is working with Poland on the possibility of Warsaw providing fighter jets to Ukraine. Some Biden administration officials privately fear that this move could be viewed by the Russians as an escalation, US officials say. Meanwhile, a multinational effort to send weapons to Ukraine is running at top speed at an undisclosed airfield in Eastern Europe, a defense official said. The US European Command is at the heart of the operation, and Joint Chiefs Chairman Gen. Mark Milley met last week with troops and personnel to examine the weapons shipments activity, the official said. Since the invasion, 14 countries have sent security assistance to Ukraine, a senior US defense official said Friday, some of which had rarely sent such substantial equipment before. Putin claimed Saturday that Russia had almost completed the destruction of Ukrainian air defense systems, and added that Western sanctions were the “equivalent of a declaration of war.” Speaking to CNN’s Jake Tapper on Sunday, Secretary of State Antony Blinken said that the US has seen “very credible reports of deliberate attacks on civilians” in Ukraine that would be considered a war crime. He added that the US is working with its allies in Europe to look into the possibility of banning Russian oil imports in an effort to further punish the country for its unprovoked invasion of Ukraine.