A MAN has admitted killing a North-East schoolboy whose semi-naked body was found in a derelict house more than two decades ago.

But Steven Grieveson today (Monday, Feb 11) denied the murder of 14-year-old Simon Martin in 1990.

The circumstances surrounding the teenager's death have remained a mystery ever since his body was found in a derelict building in Sunderland.

During a hearing at Newcastle Crown Court today (Monday February 11), via videolink to HMP Frankland, Grieveson pleaded not guilty to a charge of murder.

But Brian Hegarty, defending, told the hearing: "Mr Grieveson will not dispute that he is responsible for the death."

Judge James Goss QC told the court: "That does not mean he is admitting murder, he is admitting unlawful killing."

A trial will take place in June to determine whether 42-year-old Grieveson is guilty of murder or manslaughter.

The court heard the issues at trial may be diminished responsibility and/or a lack of intent.

Prosecutor William Lowe QC told the court: "The crown's allegation is he murdered Simon Martin, he is admitting unlawfully having killed him."

Simon ran away from his home on Amy Street, in Southwick, Sunderland, on May 18, 1990.

His body was found at Gillside House, a derelict Victorian building awaiting demolition, on the Roker coast.

Simon, who lived with his brother Robert, father Robert Snr, and mother Jean, was described as a "cheerful and friendly boy", who was a regular visitor to the amusement arcades at Roker and Seaburn.

In the wake of his death police trawled attractions along the coast trying to piece together what happened to him.

He had been battered to death with a piece of rubble.

Grieveson, who was wearing a black tracksuit top with striped sleeves, spoke only to confirm his name and say "not guilty" to the murder charge when it was read out in court.

No manslaughter charge was put to the defendant.

He was remanded in custody and will appear at court for a further hearing in March. A trial is scheduled to begin on June 24.