Alexei Navalny’s mother, Lyudmila, said she was shown her son’s body, Reuters reports.

Ludmila Navalnya also accused Russian investigators of “blackmailing” her into her son’s funeral, saying they were trying to force her to hold a private burial ceremony without anyone present.

Meanwhile, Navalny’s team said the death certificate said the Russian opposition leader died of natural causes.

She said they threatened to “do something” to his body if she didn’t agree.

“They want the funeral to take place in secret, without a goodbye. They want to take me to the edge of a cemetery, to a fresh grave and say: here is your son. I don’t agree with that,” he said in a YouTube video.

Investigators wanted to press her for the time and place of his burial, she said, adding that one told her time was not on her side as bodies decomposed.

Navalnaya is calling on the authorities to hand over his body to the family.

The Russian opposition leader died in prison last Friday at the age of 47.