Hundreds of electronic devices have been lost by officers and civilian staff of the Metropolitan Police.

A freedom of information request revealed that 24 laptops, 251 personal digital assistants and 172 BlackBerry phones were mislaid by Met Police employees in nearly five years from 2010.

At least 201 standard mobile phones were lost over the same period.

The data also showed that 301 police radios were unaccounted for.

This number includes devices that cannot be located during audits and the Met Police said that many are later found.

A Scotland Yard spokeswoman said: "We have measures in place to ensure MPS information is protected if a device is lost.

"We can take immediate action to disable a radio which is either unnacounted for or reported lost or stolen.

"It should be noted that the number of devices unnacounted for or reported lost or stolen over the course of a year is a very small proportion of the total number of devices within our organisation of around 50,000 people."

Director of the Parliament Street think thank which obtained the figures, Clare George-Hilley, said: "The loss and theft of critical equipment not only costs a significant amount of money, but it potentially puts the organisation at risk of a security breach.

"Taxpayers need to be confident that expensive devices are managed securely and kept out of reach of criminals, with officers trained to reduce and prevent these incident from occurring in the first place."

Scotland Yard was asked to provide a list of equipment reported lost or stolen, by employees including civilian and police staff over the last five years.