A 13-year-old boy stabbed a pizza shop worker to death in a row over a special offer, the Old Bailey heard.
The boy attacked Noor Kasimi with a knife after being refused a £1 pizza one hour after the promotion had ended, prosecutor Sallie Bennett-Jenkins said.
Mr Kasimi had tried to get the boy out of the Twin Star take-away in Holloway Road, north London, in September 2004 when he was stabbed, the jury heard.
The boy, who cannot be named because of his age, denies murder.
Mr Kasimi "bravely tried to help" by picking up a broom when the boy threatened the staff with a knife, Miss Bennett-Jenkins said.
Another worker picked up a stool and between them they managed to herd the boy out of the shop.
But once outside Mr Kasimi's broom fell to the floor and he was stabbed in the chest. He died six days later in hospital.
Miss Bennett-Jenkins said there was no question the boy struck the fatal blow but he claims he was acting in self defence "as he was being attacked by three men with sticks and poles.".
She said a statement in which the boy claims he stabbed Mr Kasimi with a metal pole he picked up was untrue.
The court heard the boy had gone to the pizza shop with two friends and had been "aggressive and threatening".
The owner had recognised him as having been at the shop over the last two or three days and having had problems with him, she added. "He wanted a special offer £1 pizza sold before 6pm. It was past 7pm. The proprietor said no."
She said the boy began demanding a free pizza and was again told no.
"The youth was shouting and swearing. He threatened to stab the owner.
"You may think it was no idle threat. He had gone out that night carrying a knife in his pocket."
Aabed Kashif, who ran the shop with his brother, told the court how they were struggling for their lives.
"He was still attacking us. We were trying to get him out of the shop.
"He was swinging the knife towards my brother. The broom handle broke and he swung the knife towards Noor."
The trial was adjourned until Friday.