Four teens attacked a Tooting shopkeeper and threatened to bottle him before stealing cash, booze and cigarettes.

Saheer Ponnambathayil was working alone in Jammis supermarket in Garratt Lane when the gang approached him around 11.45am on September 14 last year.

The youths, part of the well-known Henry Prince Boys gang, entered the shop and started beating Mr Ponnambathayil, punching him in the nose and head.

Ian Paton, prosecuting, told Kingston Crown Court today: "They held a bottle to his head and located £1,200 in the till and a further £500 in telephone cards. They also removed a quantity of cigarettes and spirits.

"As soon as they had taken the money, they ran away after three or four minutes. Mr Ponnambathayil then went to a nearby laundry shop where police were contacted."

The teens, Peter Benjamin, 19, of St Johns Drive, Wandsworth and Luke Sharp, 18, of Haldane Place, Tooting, and a 17 and 18-year-old, who cannot be named for legal reasons, admitted carrying out the robbery after they were caught on CCTV.

The teens, who police arrested on October 31, 2007, had all previously committed robbery.

The court heard how two of the youths, including Sharp, had converted to Islam since being in custody.

Sentencing the four, Judge Fergus Mitchell said: "There certainly seems to be some sort of gang background to this robbery.

"Ruthless violence was used in gaining money and various items from that shop. The most savage violence was used on this shopkeeper.

"This was a case of a joint enterprise so there has to be equal responsibility for the violence.

"The offence was clearly pre-planned. You knew where to get the cash and telephone cards and a number of you were wearing disguises.

"This was a vulnerable victim; there was only one person in that shop and you had to disable him temporarily by means of violence.

"I hope you don't come back to the courts in future and that you can make something of your lives."

Benjamin and Sharp were jailed for three years and the 16 and 17-year-old will spend three years in a young offenders institute.

One of the robbers is still at large.