Air raid sirens heard in the capital in the pre-dawn hours with residents urged to take shelter.
Three explosions have been heard in the centre of the Ukrainian capital, Kyiv.
Mayor Vitali Klitschko said emergency services had been dispatched to the Shevchenkivskyi district.
“Details soon,” he added on his Telegram channel.
Oleksiy Goncharenko, a Ukrainian member of parliament, said on Twitter he had heard three explosions by 6.30am local time (04:30 GMT).
The air raid alarm had gone off at 5.55am (03:55 GMT) with residents urged to stay in shelters until the all-clear.
More to come…