The shocking number of mobile phone thefts by muggers speeding around central London on mopeds has been mapped by police.

Officers in Bloomsbury – where police last year warned was a hotbed for phone snatching from criminals on two wheels – recorded a spate of 20 moped thefts in one square mile of London in just one week.

Today’s figures follow a string of reports of terrifying attempted robberies around London from scooter-riders.

Last weekend a terrified tourist was surrounded by a gang of four moped thieves in Park Lane before one of the mopeds smashes him into the pavement.

In a separate incident a moped gang were filmed tearing through the streets of London spraying strangers with a fire extinguisher.

Earlier this week hammer-wielding muggers on mopeds were also photographed targeting passers-by in the West End.

On Sunday, police in Bloomsbury released a map showing the 20 locations within one square mile where moped thieves have targeted victims in the first week of May.

Thefts have been reported near to University College London buildings as well as along Tottenham Court Road and Goodge Street. Crimes were also reported near to Great Ormond Street Hospital and towards the West End.

The phone-snatchers often mount the pavement and prey on people who are unaware they are near or perhaps using their mobile phone.

The Met have drawn up a list of around 200 people who they believe may be responsible for the majority of the moped-related crimes. But crimes such as these are often hard to prosecuted because of difficulty of securing evidence.

Last year the Met and City of London police launched a joint campaign, Operation Attrition, to combat criminals who use mopeds, motorbikes and bikes to snatch phones from victims in Camden and Islington.

They put out a warning to students at University College London, where many of the thefts were happening.

On Sunday, police in Westminster revealed they had arrested an 18-year-old man after foiling a broad daylight moped robbery in Oxford Street, at the junction with Orchard Street. Officers seized two mobile phones.