A third of Croydon's crime statistics are mobile phone thefts and they accounted for over half of street crime in 2001.

Croydon police are now backing government proposals to force handset makers to fit anti-theft devices.

The move comes as the incidence of violent muggers targeting mobile phones have soared throughout London, including Croydon, where they accounted for 52.5 per cent of street crime in 2001.

Of 2,103 recorded street crimes in the borough, including personal robbery and snatches, 1,104 involved the theft of mobiles, many from school children.

The latest incident occurred on Saturday, January 5, at 4.55pm. The 16-year-old victim was sitting on the upper deck of a number 250 bus travelling towards Thornton Heath, when three youths asked to see his phone.

When he refused, he was punched in the face, knocking three teeth out, and his Nokia phone was stolen. The attackers boarded the bus at Streatham Common, and are described as black males, aged around 16. They fled down Hawthorn Crescent, while the victim was taken to Mayday Hospital and later had his teeth replaced.

Now the government is considering legislation which would force companies like Nokia to install gadgets which could make stolen phones unusable, once the theft is reported.

Chief Inspector Derek Millar told the Guardian: "We welcome anything that will help reduce the theft of mobile phones and the threat to people that own them.

"It's a serious problem right across London and Croydon is no different."

Croydon has already moved to curtail the rising tide of phone theft by launching Operation Phonebill in March, which saw officers visit all 37 secondary schools in the borough, marking pupils' phones to make them less attractive to thieves.

Chief Insp Millar said: "Operation Phonebill was an initiative that was born out of the fact that the mobile phone operators were not willing to make them less easy to steal.

"It's too early to say at this stage how successful the operation has been."

Anyone with information relating to the bus attack should contact South Norwood Robbery Squad on 020 8649 1362.