A series of blasts were heard in the Ukrainian capital, Kyiv, shortly after midnight local time on Tuesday, AFP journalists said, after the authorities warned of several approaching missiles. The reporters said they heard several loud explosions while the city’s mayor, Vitali Klitschko, wrote on social media that Kyiv was “under ballistic missile attack”. Klitschko said emergency services had been sent to the Shevchenkivsky district, without providing further details. Air raid sirens had begun to sound shortly before the blasts were heard. President Volodymyr Zelensky had earlier said that Russia was preparing to deploy more North Korean troops in the war and had received new ballistic missiles from Pyongyang. Moscow has stepped up its ballistic missile strikes in recent weeks, which only certain air defence systems, including US Patriots, are capable of intercepting. The shortage of PAC-3 interceptor missiles has worsened since the war launched by the United States and Israel against Iran in February. At the same time, Ukraine has been increasing its strikes against Russian cities far from the border.