A trio of robbers who terrorised Twickenham during a half hour rampage have been jalied for four years in the borough's first case of steaming'.

The 16 and 17 year olds, who cannot be named for legal reasons, were part of a gang who robbed and threatened anyone who crossed their path during spree, in a crime dubbed as steaming'.

The youths, one disguised by a balaclava, threatened or robbed nine victims on a route between Twickenham station and Richmond upon Thames College on January 11 this year at around 4pm.

Detective Inspector Mark Cranwell explained: "The group were winding through the crowds of people, intimidating and robbing anyone who got in their way. They went up various people and tried violence. It was a pretty horrific offence."

When the three youths, who came from the Brixton area, were sentenced for conspiracy to rob at Kingston Crown Court, two of the gang were jailed for three-and-a-half years and the ringleader was given four years.

One of the victims was a 16-year-old student who was set upon as he walked to the station from the college. They punched him to the ground when he refused to give them his Ipod, then punched and kicked him as he lay on the floor. They were arrested by police at 4.30pm.

The Richmond policeman who led the case, Detective Constable Richard Gilbert, has been praised for his work in bringing them to justice, in what has been described as a complex investigation, because of the number of victims and suspects.

DC Gilbert said: "Given that they were all 16 or 17 at the time of the offence and none had any previous convictions, this is a pleasing result and a strong message to others."

The prosecution barrister at the trial, Rory Keene, praised the officer's work. He said: "The case was put together immaculately by DC Gilbert who had obviously spent a great deal of time reviewing the CCTV evidence that allowed me to present the case before a jury in a seamless fashion.

"My experience of police officers is generally very positive, in the case of PC Gilbert he is an absolute credit to the police force in terms of his professionalism diligence, ability to deal courteously with the members of the public and the defence team concerned. But for the dedication to this job, the defendants may well have been acquitted."