Two British detectives investigating the 1984 murder of a policewoman outside the Libyan embassy in London have visited Tripoli for talks with Libyan officials, Scotland Yard said Thursday.
Counter-terrorism officers were in Tripoli from Monday to Wednesday to discuss how the investigation could be taken forward, the police said.
Yvonne Fletcher, 25, was shot dead outside the Libyan embassy while policing peaceful demonstrations. No one has ever been charged with her murder.
The fatal shot was always believed to have been fired from inside the building, sparking an 11-day stand-off with police.
However, investigators suspect that the killer left Britain among the 30 staff who were subsequently deported but who enjoyed diplomatic immunity.
"We hope these preliminary discussions will pave the way for the Metropolitan Police Service and Libyan authorities to work jointly to identify who was responsible for Woman Police Constable Fletcher's murder in 1984," Scotland Yard said in a statement.
"Detectives remain in regular contact with WPC Fletcher's family who will be given an update about the visit."
The killing led Britain to cut diplomatic relations with Libya until 1999.
Along with the 1988 bombing of a passenger jet over the Scottish town of Lockerbie, it has been a long-running strain on ties between London and Tripoli.
Britain was one of the leading countries in the NATO-backed military campaign that helped topple Libyan leader Moamer Kadhafi, who was killed in October by rebels.
London believes the overthrow of Kadhafi's regime has given investigators a much better chance of bringing a suspect to justice.
On a visit to London last month, Libyan interim Prime Minister Abdel Rahim al-Kib pledged that his country would work closely with the British police to resolve outstanding questions about the murder.
He laid a wreath of white roses and carnations in St James's Square at the spot where Fletcher was shot dead.
Kib worked with the opposition while in exile during Kadhafi's rule and said he knew some of those involved in the demonstration.