Kyiv came under heavy drone and missile attack early Sunday in what independent monitors say was one of the biggest Russian strikes on Ukraine’s capital and the surrounding region since the full-scale war began.

Drones flew over the city and anti-aircraft fire rang out through the night. The attack was continuing at 7:20 a.m. (0420GMT). Kyiv’s military administration said at least six people had been injured as of 0440 GMT.

Some residents fled to metro stations deep underground for safety. Many regions across the country were under air raid alert, while neighbouring Poland closed airspace near two of its southeastern cities and its air force scrambled jets in response.

Meanwhile, President Volodymyr Zelenskiy has said Ukrainian officials will visit the United States for talks on major arms purchases and drone production deals.

Zelenskiy was in the United States this week for the UN General Assembly and to meet US President Donald Trump.

He said he had shared with Trump “a certain vision of what could be done” to respond to Russia’s actions in its war on Ukraine.