EDMONTON - A Russian-born Edmonton martial arts enthusiast has admitted fatally stabbing his mother in the jugular vein with a shard of glass in a fight at their west-end home.

And, according to court documents, Rostislav Soukonnik confessed to being in a "fit of rage" when he punched his mom, repeatedly slammed her face-first into a heater while holding her by her hair and then put a couch on top of her body, sitting on it for 20 minutes before calling 911.

As well, court documents obtained by the Edmonton Sun reveal the victim -- 60-year-old Maia Soukonnik -- called 911 herself shortly before the deadly attack. However, police failed to respond to the call.

Soukonnik, 21, pleaded guilty to manslaughter Friday morning in Court of Queen's Bench.

He had been charged with second-degree murder in the Nov. 13, 2008, slaying, but the Crown agreed to let him plead guilty to the lesser and included offence.

A pre-sentence report and psychiatric assessment were ordered. A sentencing hearing was set for June 1.

Court heard agreed facts will be presented that day.

According to a transcript of the preliminary hearing held in the case, Soukonnik confessed near the end of a six-hour interview with homicide Det. Dennis Storey to killing his mother during a fight at their 9023 184 St. suite.

Soukonnic said an argument between them led to a physical fight during which his mother threatened to kill him.

"We started kind of attacking each other and I happened to win, OK," said Soukonnik in the videotaped interview.

He revealed the glass shard he used to stab his mom in the jugular -- which led to the victim suffering a fatal air embolism -- came from the broken glass in a smashed framed painting of his father, who died when he was 12.

He later told the detective he "couldn't stop" and said it was an "accident" and he hadn't meant to kill her.

"What's the matter with me? How could I do this to my own mother," he told Storey.

Under cross-examination, the detective agreed the victim had made a 911 call prior to being killed, but police did not respond. He also said there was a review into it.

Court heard Friday Soukonnik has a psychiatric history.

According to the preliminary hearing transcript, a member of the police crisis team monitored Soukonnik's interview and said he appeared "lucid and coherent."

However, earlier when emergency crews responded to the scene, a paramedic said Soukonnik was acting strange, talking about gang members trying to poison him.

The crisis team officer testified at the preliminary hearing he had dealt with Soukonnik a year earlier and said the man had told him he had "special powers," super-human strength and could read his mind and levitate.

He also said he was an expert in martial arts and was going to be trained for a government special forces unit.

The officer called it a "grandiose delusion" and said Soukonnik also admitted using illicit drugs.

At the time of the slaying, police seized a samurai sword -- bent into an S-shape -- which lay on the ground below an open window of Soukonniks' suite. In the police interview, Soukonnik said he had bent it on his own neck.