Tablets and handsets seized as evidence by police are being remotely wiped clean of their data, according to a BBC investigation.
Forces in Cambridgeshire, Derbyshire, Nottingham and Durham all reported cases in which data on confiscated mobile devices had been purged.
A spokeswoman for Dorset police, which suffered six such incidents, said the force did not know how people had managed to wipe them, but the technology had the ability to allow users to remove data if the devices were stolen.
"We have cases where phones get seized, and they are not necessarily taken from an arrested person - but we don't know the details of these cases as there is not a reason to keep records of this," she told the BBC.
One phone was remotely wiped while in the possession of Derbyshire police.
The force would not share details about the incident other than the phone being involved in a "romance fraud".
A spokeswoman said that this did not impact the case and a conviction was secured regardless.
Cleveland police also reported a phone that had been wiped, although the force said it did not know if it had been "wiped prior to coming into police hands".
Police forces in Cambridgeshire, Durham and Nottinghamshire also reported one such data wiping incident each.
Ken Munro, a digital forensics expert with Pen Test Partners, told the BBC that if a device receives a signal it would be possible for it to be remotely wiped.
He added that if a device is seized for forensic examination, it needed to be placed in a radio-frequency shielded bag to prevent any signals from reaching it.
Failing that, placing it in a microwave oven was a good alternative until it could be put in a shielded bag, he explained.
"The microwave is reasonably effective as a shield against mobile or tablet signals - just don't turn it on," he told the BBC.
