LONDON (AP) -- British police have arrested a Libyan man in his 50s on suspicion of conspiracy to murder in the 1984 killing of London policewoman Yvonne Fletcher.
They said it is "the first significant arrest" in the investigation into the killing of the 25-year-old policewoman more than 30 years ago.
Fletcher was killed and 10 others were wounded when someone inside the Libyan embassy in London opened fire on police and protesters on the square outside.
The killing led Britain to break diplomatic relations and helped seal Libya's reputation as a rogue state under Moammar Gadhafi's harsh rule.
Police said Thursday they had also arrested a man and a woman for suspected money-laundering offenses related to the complex case.
Commander Richard Walton, head of Scotland Yard's counter-terrorism unit, said the three were arrested Thursday morning.
"Over the past 31 years we have never lost our resolve to solve this case, to bring to justice those who conspired to commit this act of murder," he said.
The three were arrested at separate addresses in London and southeastern England.
Police said the money-laundering suspects are also Libyans and that the woman is in her 40s and the man is in his 30s.