Vandals have damaged a memorial to a police officer who was murdered in the line of duty, police have said.

Pc Ian Broadhurst, 34, was shot dead by the former US marine David Bieber, 42, on Boxing Day 2003.

West Yorkshire police said paint appeared to have been thrown over the stone memorial, which stands in the Fearnville area of Leeds, towards the end of last week, since when it has been cleaned up.

Pc Broadhurst's colleagues, Pc Neil Roper and Pc James Banks, were shot and injured that day after they pulled Bieber over for driving a car displaying false number plates.

The American bodybuilder, who was wanted by the FBI for ordering two killings in Florida, was found guilty of murder and two counts of attempted murder in 2004 and was jailed for life, with a recommendation he should never be released.

In 2008 Appeal Court judges said Bieber should serve a minimum of 37 years in prison before being considered for parole.

Chief Superintendent Richard Jackson said: "Police officers go to work every day never knowing what could happen, and thankfully few never make the ultimate sacrifice made by Ian Broadhurst.

"The memorial is a way for local people, local officers and Ian's friends and family to mark the terrible events of December 26 2003, and for someone to deliberately vandalise the memorial is about as despicable as it's possible to get.

"I would ask the local community to come forward with any information they may have on those responsible so we can ensure they are brought to justice."

Anyone with information is asked to contact the Killingbeck and Seacroft Neighbourhood Policing Team on 101 or call Crimestoppers on 0800 555 111.