A BBC investigation has found that many mobile shops in London are willing to purchase phones that they know are stolen, even giving tips on how to remain uncaught.

Posing as thieves, an undercover BBC London researcher visited shops across east London. He attempted to sell Samsung Galaxy S3 and iPhone 4s and found that there was no problems whatsoever in finding buyers, even when the phones were locked and featured messages on their screens saying things like, "This mobile has been stolen. You have been reported to the authorities."

The researcher even told one shop, "I not buy, I steal, yeah?" The assistant in London Mobiles in Ilford still bought the phone.

READ: Tips to prevent your iPhone or Android phone from being stolen and what to do if it is

Other shops also bought phones from the BBC undercover reporter, with one saying, "You're mental man, just turn it off, they can track you... they got SIM card inside, throw away the SIM."

John O'Connor, former commander of the Metropolitan Police's Flying Squad said: "You have got people so confident and so casual in dealing with what they believe to be stolen property - and encouraging robberies.

"By providing a conduit for the thieves to be able to convert those stolen phones into money, they're encouraging the commission of offences."

The UK's Police service has its own National Mobile Phone Crime Unit, which claims that between quarter of a million to 300,000 mobile phones are stolen in the country every year. With shops so willing to buy them, are we surprised?