Ponomaryov, 48, fled to Ukraine and gained citizenship after opposing Moscow's annexation of Crimea.

Ponomaryov said that he was hurt by an overnight drone attack on his house near Kyiv.

"This thing blew in very forcefully, right in front of the threshold of the house, and loads of shrapnel flew into me," Ponomaryov wrote on Facebook.

He said that the attack happened at night after the all-clear had sounded and that he did not hear air defences firing at the drone.

He posted photos showing fragments of a Russian Shahed drone, trees cut by an attack and a crater in a paved area.

"My guards ran up and put out the fire quickly but there was a lot of blood and I had to go to hospital very quickly," he said.

He said that he was around five metres "from death" and that the attack came after drones were downed near the house on Tuesday night, blowing out several windows.

Ukraine's National Police said a drone attack on Thursday morning in the Kyiv region wounded a man and his wife, who were hospitalised, and damaged two private houses.

It posted a photo of a large house with windows blown out and damaged roof and balconies.

A police spokesperson told AFP that she could not disclose personal data of those injured.

Ponomaryov was a Russian lawmaker from 2007 to 2016 and was the only MP to vote against the annexation of Crimea.

Charged with embezzlement shortly after, he went into exile and obtained Ukrainian citizenship.

Until this week he headed the political wing of the Freedom of Russia Legion, a unit of ethnic Russians who are fighting on the side of Kyiv and have carried out armed raids across the border.

The Legion had announced Wednesday that it had unilaterally cut ties with Ponomaryov and no longer had a political wing.

"Unfortunately in these two years we have not managed to reach the announced political aims," it said on Telegram.

Ponomaryov wrote on Facebook that "Russian authorities have been trying to get me for a long time" and that he has "very serious guards" after four assassination attempts.

Ukraine's air force said Thursday that its forces downed seven drones overnight including in the Kyiv region.