Libya's former head of intelligence holds the key to solving the murder of policewoman Yvonne Fletcher, the Libyan prime minister has claimed.
Abdurrahim El-Keib, who on Friday visited the spot where Wpc Fletcher was shot dead outside Libya's London embassy in 1984, said Abdullah al-Senussi was the "black box" who would know who carried out the killing.
Senussi, one of Muammar Gaddafi's most senior henchmen, fled Libya last year and was arrested in Mauritania in March. He is wanted by the International Criminal Court for crimes against humanity. He is also suspected of involvement in the Lockerbie bombing.
Mr El-Keib, Libya's interim prime minister, told The Guardian: "He's the black box.
"I guarantee he was almost directly or indirectly involved in most if not all of the crimes (of the Gaddafi regime). That doesn't mean others weren't involved. But he definitely knows who they were."
It was announced this week that a team of detectives from the Metropolitan Police would fly to Libya to continue their investigations into the unsolved murder.
Mr El-Keib also said his country would "work very closely together" with the UK after talks with Prime Minister David Cameron.
Wpc Fletcher, who was 25, was shot dead as she policed an anti-Gaddafi demonstration outside the Libyan People's Bureau.
The bullets which killed her and injured 10 protesters came from inside the embassy.
Her death led to an 11-day siege of the building in St James's Square and the severing of diplomatic links between the UK and Libya.