A TEENAGER who was part of a gang that pushed a firework through the front door of a house, which then went up in flames, killing a father, admitted man-slaughter yesterday.

The court was told the youth - who was 15 at the time and cannot be named for legal reasons - had confessed to friends: "We didn't mean it. It was only a little joke. I can't understand how it's done that much damage."

Judge David Hodson warned him: "You must appreciate for an offence of this nature the overwhelming likelihood is a period of custody."

Arthur Lonsdale died while trying to flee his burning house after the firework was pushed through the door as a prank, Newcastle Crown Court was told.

Shortly before the tragedy a group of youths were seen in the area and fire crews later found the remains of a Little Brother rocket near the back door of Mr Lonsdale's Sunderland home.

Mr Lonsdale, 52, was overcome by smoke and fumes and was found collapsed in the doorway.

When firefighters arrived at the divorcee's end terrace home in Westerham Close, on the city's Witherwack Estate, the property was engulfed in flames.

Crews had to use special equipment to fight their way into the property.

The court heard the rocket became lodged beneath a fridge-freezer and spread flames to nearby newspapers and a bean bag.

Mr Lonsdale, a former locksmith who had two children, was still breathing when help arrived.

But due to the effects of acute smoke inhalation he died in hospital two days later.

He had set up a cat sanctuary at his home. All his pets perished in the blaze.

Brian Forster QC, prosecuting, told the court: "The Crown have always and still put the case on the basis the defendant was one of a group of young people who went to that house.

"We do not attempt to say it was this defendant who carried out the physical act of putting the rocket through the cat flap."

Mr Forster told the court how youths had been congregating in the area in the weeks leading up to Guy Fawkes night and rockets being let off in the street had been common place.

Mr Forster said: "Fireworks had clearly been on sale for some considerable time because on September 1, police had seized Little Brother rockets from a group of youths in Witherwack.

"People living in the estate had seen a gang of youths congregating. Fireworks would be thrown and they were making themselves a nuisance.

"It is the prosecution's case the defendant was one of that group who met on the estate and who had fireworks in their possession."

The 16-year-old will be sentenced on September 5 after the preparation of reports. He was granted conditional bail.