Police in St. Petersburg arrested a prominent Russian historian suspected of murdering a former student after he came out of a river with a backpack containing a woman's arms, announced the authorities.

Local media in St. Petersburg reported that Oleg Sokolov, a university professor, was drunk and fell into the river while he was trying to get rid of his body parts on Saturday.

The police then reportedly went to Sokolov's home, where she discovered the decapitated body of 24-year-old Anastasia Yeshchenko, with whom he had co-authored several works.

"A 63-year-old man was rescued from the Moika River," investigators said.

A woman's arms were found in her backpack, the statement said, adding that the arrested man was suspected of murder.

The investigators did not name the man, but the police spoke with AFP and identified him as Sokolov.

The historian is the author of books on the French statesman and the military leader Napoleon Bonaparte. He played the role of history consultant for several films.

He received the French Légion d'Honneur in 2003.

Sokolov was also a member of the French Institute of Social, Economic and Political Sciences (ISSEP), but the company said Saturday in a statement that he had been removed from his position on its scientific committee.

The ISPEP was founded by Marion Marechal, niece of Marine Le Pen, leader of the far-right National Rally party and former MP of this party.