AN OBSESSED student was responsible for brutally killing a 15-year-old girl, a jury decided.

Arsema Dawit's blood-drenched body was found slumped in a lift at the Waterloo tower block where she lived after being stabbed more than 30 times.

Defendant Thomas Nugusse, 22, was found unfit to plead in the trial after suffering brain damage in an attempted suicide in custody just days after the attack.

He was revived twice by staff at Bedford Prison after trying to hang himself.

As a result, the Old Bailey jury was asked only to decide if Nugusse was responsible for the killing in June last year.

Nugusse killed Arsema on June 2 last year, despite her mother warning the on many occasions police that he posed a threat.

Nugusse, of St Francis Way, near Aldersbrook, was sent to a mental hospital without limit of time.

The jury was not allowed to return conventional innocent or guilty verdicts and instead found that Nugusse "committed the acts".

Nugusse and Arsema had been in a relationship for two years but she ended it after his behaviour became too much for her.

The jury had been shown CCTV footage of Nugusse following Arsema towards her home and also heard a tape of the 999 call in which Nugusse admitted killing her.

In it he said: "I had a fight with my girlfriend and I killed my girlfriend. My name is Thomas. She is in Waterloo, I don't know the address. I killed my girlfriend. Her name is Arsema."

Nugusse had previously studied at Chadwell Heath-based Redbridge College in 2005 but a spokesman for the school was unable to reveal any details when approached by the Guardian at the time of his arrest in June, 2008.

Speaking at the time he said: “All I can confirm is that Thomas Nugusse was a student at Redbridge College for one year three years ago.”

Mrs Medhane complained that officers had failed to save her daughter. An inquiry has been ordered by the Independent Police Complaints Commission.

She made a statement in which she said Nugusse had called threatening Arsema and said he would find her and kill her.

Mrs Medhane went to Kennington police station and asked officers to arrest him.

She told the judge in a statement: "I have lost hope. My daughter is constantly in my mind.

"She was my precious child and there are no words to express how I feel. The house feels empty."