A 22-year-old Russian man has been arrested on suspicion of murder after the tortured remains of his teenage estranged wife were found in a river.

Olga Onipenko, 18, had been beheaded and her innards gouged out of her corpse which was found near the city of Astrakhan, close to the border to Kazakhstan.

The estranged couple had rowed over their nine month old son in a tug of love dispute after they split, said friends.

Murdered: Olga Onipenko, 18, was allegedly killed by her estranged husband Viktor Onipenko, 22, who has since confessed to the murder

Viktor Onipenko, 22, has confessed to murder, according to police, but his relatives insist he has been framed and was not capable of such violence.

The wife's body was found in the River Krivaya Bolda several days before her head was located, said police.

Initially, she was identified by a tattoo.

Police claim that during a row over custody of the child he grabbed a knife and stabbed her in the stomach and back, according to a report on major television channel NTV.

'Then he gutted her innards and beheaded her, throwing her remains in the river,' said a police source.

Mrs Onipenko, 18, had been beheaded and her innards gouged out of her corpse, which was found near the city of Astrakhan, close to the border to Kazakhstan

Battle: The estranged husband and wife had allegedly been fighting over the custody of their child

Gruesome: The 18-year-old's body was found several days before her head and she had to be ID'd by tattoo

The child is now in an orphanage in Astrakhan region, on the shore of the Caspian Sea.

Lyudmila Tsyganova, a friend of the dead woman, said: 'They constantly argued over their child and he threatened her.'

The had parted but her husband had defied a judge and kept custody of the child, refusing to allow her to see the baby.

The couple had been together since she was 13 and she was pregnant at 16.