A gang of angry youths "tormented" a terrified bus driver who had to seek counselling after she thought she would be shot.

A 15-year-old boy from Mitcham, who cannot be named for legal reasons, was convicted by Wimbledon magistrates court yesterday of possessing an imitation firearm with intent to cause distress.

The teenager, who has a previous conviction for bringing a weapon into school in 2007, denied concealing what appeared to be a gun in the waist of his trousers while boarding the 200 bus in Fair Green on July 25, 2011.

The court heard a recording of the distressed bus driver, Jenny Green, make an emergency "code red" call to her colleagues after she refused to let the boy and his two friends travel for free without a pass.

During the incident she said: "There is a gang of boys... they've got some sort of gun as well."

When asked by her colleague what type of gun, she shouted: "I don't know, I don't work in the army - I think it might be some sort of pellet gun."

Mrs Green told the court how the boys began calling her abusive names after being told to leave the bus, when the defendant revealed a gun handle.

His friends then sought revenge on the driver by turning off her bus engine with an external switch on the rear of the vehicle, the court heard.

After leaving the bus, the boy's friend was heard to say "just shoot her" while the boy himself appeared to be waving what looked like a gun.

The court did not accept the teenager's explanation that the bus driver merely saw him pointing to a friend who had remained on the bus.

Kathryn Selby, prosecuting, said: "You and your friends continued to torment this bus driver by switching off the engine... You wanted to scare her."

The driver also told the court she had to receive counselling following the incident, was off work sick for six weeks, and no longer drives buses through Mitcham.

Detective Constable Dan Kelly, from British Transport Police, said it was thanks to a Wimbledon Guardian reader that the boy was identified after an appeal was launched following the incident.

The teenager was found guilty and will return to court with unconditional bail on March 29, when he will be sentenced.

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