Police are warning people not to use their iPhones while walking Islington’s streets - because thieves on bicycles and mopeds have struck more than 100 times in the past month alone.

Teenager gangs are prowling the streets around Angel and Old Street Tube stations on two wheels, before pouncing on commuters as they talk, text or check the internet on their smart phones.

There has been a 400 per cent rise in incidents compared to the same period last year.

Detective Sergeant Harry Kooner, from Islington robbery squad, said: “It may sound horrible but we are telling the public not to use their phones when they are out walking the streets, unless they have their back against a wall and can see what’s going on around them.

“Most of the snatches have happened on major arterial routes around Angel and Old Street Tube stations - such as Upper Street, Essex Road and City Road.

“The thieves know people often text before they get on the Tube, or get straight on the phone when they come out of the station, and they are just riding up on the pavement and grabbing their iPhones before people know what is happening.

“They are then selling them for more than �100 a go so.

“We have charged three teenagers so far but we are still investigating and need people to be on their guard.”

- Anyone with information should call the robbery squad on 020 7421 0250.