Kent Police are pursuing a number of leads following a burglary at Sevenoaks-based Forensic Telecommunications Services (FTS) in which a server containing data on suspicious telephone calls over the past two years was stolen.
A police spokeswoman said, "The computer equipment contained evidence relating to telephone use linked to around 250 cases from police forces and law enforcement agencies across the UK, covering the last two years.
She declined to say whether the data was encrypted.
Acting chief constable, Adrian Leppard, said, "We are keeping an open mind at this stage as to the motive behind the burglary. However, we and the company have informed other police forces."
"Our understanding is that almost all information on the stolen computer equipment relates to cases where the evidence has already been disclosed to defence solicitors. No evidence has been lost, as the company keeps back-ups," Leppard said.
A spokesman for FTS declined to provide any details beyond a prepared statement.
However, a Mail on Sunday report said the cases were related to counter-terrorism investigations.
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