By Steven Shukor BBC London

Five boys have been found guilty of the manslaughter of a 67-year-old man who suffered a heart attack when he was pelted with stones by a mob.

Linda Norton says she feels no anger towards the boys

Linda Norton clung tightly to her son James as they watched an off-duty policeman try to save her husband's life.

But the officer's resuscitation attempt was in vain and Ernest Norton died outside Erith Leisure Centre in south-east London.

At the time Mrs Norton had no idea her husband had been pelted with stones by a young mob moments before he collapsed.

"I called out to Ernie and took his hand," she said. "I stood back and let them get on with it. I was just holding on to my son."

She had rushed outside from the leisure centre gym when 17-year-old James told her of his collapse on 22 February 2006.

"The only thing that was going through my mind was that he had had a heart attack," said Mrs Norton.

To have died in such an angry sort of way... it's still taken a while to sink in, even after all this time Linda Norton Boys guilty of manslaughter

Mr Norton had had a triple heart bypass operation 30 years ago due to a congenital condition, although he was active and in good health.

"I didn't know anything about what had happened beforehand," she said.

The 67-year-old had suffered a heart attack after he was assaulted by a gang of up to 20 boys as he practised bowling a cricket ball with James in the tennis court.

The group approached the pen and began shouting abuse and throwing stones and rocks - as big as half a brick - hitting Mr Norton on the head twice.

Mr Norton was practising cricket with his son in the tennis courts

He collapsed unconscious with a shattered cheekbone and a bleeding head. The stress and the trauma of the attack is said to have triggered the heart attack.

"To have died in such an angry sort of way... it's still taken a while to sink in, even after all this time," said Mrs Norton.

"It's not a nice way to have ended his days."

Five boys, aged between 10 and 13 at the time and with no previous convictions or cautions, had denied manslaughter and violent disorder.

No anger

They were among the youngest defendants to appear at the Old Bailey and stood in the dock with their parents.

Mrs Norton said she did not feel any anger towards to them and accepted they did not set out to kill her husband.

"I think it was just the way it turned out," she said.

Inside you're fighting it down all the time how you really feel Linda Norton

"It probably started off as banter, but there is still no excuse for throwing stones."

She blames the mob attack on a minority of troublemakers leading other children astray.

"They need something that they can do in the evenings and at weekends that's of little expense to parents."

She said she has had to be strong for James and avoid wallowing in sorrow.

"I've been bearing up under it all," she said.

"[My family] have been very surprised. But inside you're fighting it down all the time about how you really feel."