London: A British police force has issued an alert to its staff after receiving terrorist threats to kidnap and murder one of its officers.
West Midlands Police, based in the north of England, said it is investigating an "anonymous but credible" tip-off.
Assistant Chief Constable Garry Forsyth stressed the "additional safety reminder" for staff did not pose any additional risk to the public.
"There is nothing at this time to suggest there is an increased risk to members of the public," he said.
"We have taken the opportunity to remind all employees of the need to be vigilant. Our priority remains serving our communities and protecting them from harm.
"Officers remain on patrol and our staff continue to respond to calls for service as usual," he added.
The threat level to police officers across Britain was raised to substantial in October, meaning an attack is a strong possibility.
A West Midlands Police spokesperson confirmed counter-terror officers were continuing to assess the anonymous information the force had received.
Officers were held on duty while they were given the security reminder as they started their shifts.
The advice included guidance about travelling to and from work in partial uniform and police station security.
Meanwhile, Scotland Yard commissioner Sir Bernard Hogan- Howe said his force had not issued guidance to officers, but was analysing the threat.
"Once we've assessed it, we'll decide whether or not to give any further advice," he said.
The UK Home Office declined to comment, describing the threat as "purely an operational matter for the police".