For the first time since the war in Ukraine began, a safety corridor had been used to successfully evacuate thousands of civilians trapped inside the town of Sumy in north-eastern Ukraine.

However, just hours before that, at least 21 people, including two children, were killed in Russian airstrikes on the town.

“In some localities residential buildings were bombed,’’ Dmytro Zhyvytskyi, head of Sumy’s regional administration, said in statement posted on Facebook on Wednesday, adding that several buildings had been destroyed when a bomb exploded near the city centre.

Four Ukrainian soldiers were killed in what Mr Zhyvytskyi described as “unequal combat with the Russian military.’’

The information could not be independently verified.

The Russian military enforced a ceasefire earlier on Tuesday and opened so-called “humanitarian corridors’’ in five cities. These include the capital Kyiv, the major cities of Chernihiv and Kharkiv, Sumy and the particularly embattled port city of Mariupol.

According to the deputy head of the Ukrainian President’s Office, Kyrylo Tymoshenko, 61 buses left Sumy for Poltava on Tuesday.

Among the passengers were some 1,100 foreign students, he said.

Around 5,000 Ukrainians and around 1,700 foreign students were taken to safety on Tuesday, Deputy Prime Minister Iryna Vereshchuk said, according to the Ukrainian news agency UNIAN.

The escape routes led to localities including Poltava in central Ukraine, Lviv in the west and neighbouring EU countries.

The Ukrainian Foreign Ministry in Kyiv shared a video showing civilians with luggage sitting in minibuses filled with water bottles. Cars joined the convoy.

Sumy is only about 30 kilometres from the Russian border, for days, the town had been under attack by Russian troops.

For other encircled cities such as Mariupol or Volnovakha in eastern Ukraine, several attempts to establish a so-called green corridor had failed in recent days.

Both sides blamed each other for the failure to respect the ceasefire.

Four Ukrainian soldiers were killed in what Mr Zhyvytskyi described as “unequal combat with the Russian military.’’

The situation in Mariupol is considered particularly critical 13 days after the start of the invasion.

According to the Red Cross, 200,000 people were still trapped in the city hoping to escape.

Fresh attempts at opening safety corridors were planned for Wednesday, with Mikhail Mizintsev of the Russian Defence Ministry announcing that a ceasefire would come into effect on Wednesday at 8:00 a.m.

He added that this would remain open until 1:00 a.m. for evacuations. Ukraine did not immediately respond to the announcement.

Ukraine’s Infrastructure Minister, Oleksandr Kubrakov, estimated the damage wrought so far on Ukraine’s transport infrastructure by the Russian invasion at more than $10 billion.

Another round of talks between Russia and Ukraine is expected on Thursday.

Earlier, in an interview with U.S. broadcaster ABC late on Monday, President Volodymyr Zelensky expressed his willingness to hold talks on the status of the separatist regions in the east and the Crimean Peninsula, annexed by Russia in 2014.

“I am ready for a dialogue, we are not ready for capitulation. We can discuss and find a compromise on how these territories will live on,’’ Mr Zelensky said.

Mr Zelensky acknowledged that Russia had air sovereignty over Ukraine and reiterated a call for a no-fly zone over his country’s territory.

The NATO military alliance “is afraid of controversial things and a confrontation with Russia,’’ he pointed out.

He hinted Ukraine could refrain from joining the defence alliance, but insisted that it was not a country on its knees begging for anything.

NATO accession has been Ukraine’s stated geopolitical goal since a constitutional amendment in 2019.

Meanwhile, CIA director William Burns has told a U.S. Congressional hearing that he believed President Vladimir Putin was angry and frustrated right now, and predicted the fighting in the cities could be even worse than before in the coming days.

But U.S. President Joe Biden, who on Tuesday imposed a ban on all imports of crude oil from Russia, said Mr Putin would never emerge victorious from his invasion of Ukraine.

Mr Putin might be able to take a city, but he would never be able to hold Ukraine, Mr Biden asserted, adding that Russia will emerge from the war weaker, while the rest of the world would be stronger.

(dpa/NAN)