Alexei Navalny was killed by KGB's lethal 'one-punch kill' technique: activist

As the mystery surrounding Alexei Navalny's death continues to spur speculations, a human rights activist has claimed that the Putin critic was killed with one punch to the heart—an infamous method once used by former Soviet spy agency KGB.

The 47-year-old had died last week on Friday while serving a 19-year sentence at the Arctic prison colony. Navalny's spokeswoman Kira Yarmysh had earlier claimed that his body was covered with bruises, indicating that he was murdered.

Russian-born human rights activist Vladimir Osechkin told The Times that the bruising found on Navalny's body was similar to the "one-punch" technique previously taught to KGB special forces operatives.

He further claimed that the 47-year-old was made to spend over two and a half hours outdoors in an open-air solitary confinement space where temperatures were as low as minus 27 degrees Celsius.

Osechkin claimed that this information came from a source working in corrective colony FKU IK-3—also known as the Polar Wolf jail— where Navalny died.

"It is an old method of the KGB's special forces divisions," Vladimir Osechkin, founder of the human rights group Gulagu.net, told the Times of London.

"They trained their operatives to kill a man with one punch in the heart, in the centre of the body. It was a hallmark of the KGB," Osechkin was quoted as saying.

"I think that they first destroyed his body by keeping him out in the cold for a long time and slowing the blood circulation down to a minimum.

"And then it becomes very easy to kill someone, within seconds, if the operative has some experience in this.

Russia’s Federal Penitentiary Service initially said that the Putin critic had “felt unwell” after taking a walk in the prison, “almost immediately losing consciousness”, and that medical staff were unable to save him.

A state-controlled channel on Telegram claimed the same day that he had died of a blood clot.