Police have launched a new operation to tackle a spike in robberies, especially of mobile phones and cash from schoolchildren.

A new police unit has been formed as part of Operation Zeus, which was launched last week and will run until the beginning of April.

The unit will be made up of 12 officers and three sergeants with additional support coming from Croydon’s Crime squad.

Detective Inspector Brian Hobbs heads up Croydon’s robbery department and is in charge of Operation Zeus. He said the officers would be primarily undercover, use stop and search tactics and disrupt robber’s patterns of behaviour.

Robbery offences have risen in Croydon over the past year, with an increase of 11.7 per cent up to the end of December last year.

Recent figures show that from December 14 last year to February 8 this year, 268 robbery offences had taken place, with the majority of victims schoolchildren aged 11 to 15.

Property stolen is almost exclusively mobile phones and cash, with Oyster Cards and jewellery also taken.

The majority of incidents took place between 4pm and 8pm.

The aim of the Operation is to reduce robbery by 10 per cent for the same period last year, and solve 15 per cent of crimes.

The number of personal robbery cases in Croydon rose from 1,632 in 2011 to 1,823 in 2012.

DI Hobbs said more resources are being put into catching robbers. He explained there will be eight robbery reporting cars available, a small unit who will have responsibility for reporting all allegations of robbery between 8am and 10pm.

He said Croydon has a high volume of robbery offences due to its large population but the crime rate was average.

In the first week of the operation they solved more than half of the robberies that took place.

DI Hobbs said: "Robbery is a priority crime and we recognise it as one of the most serious crimes that can happen as it is extremely distressing for victims.

"Croydon is not a bad place to live. The key thing is to report things to us and report it as quickly as possible."