Robert Duff murder probe begins five years after disappearance
A murder investigation has been launched five years after a father-of-two disappeared.
Robert Duff has not been seen since he failed to attend his daughter's 18th birthday celebrations on 12 January 2013.
Mr Duff, who was 37 years old at the time, was last seen that day withdrawing money from an ATM outside a supermarket on Holloway Road.
Police now believe he was killed the same night after getting into a fight.
Two men, aged 70 and 51, were arrested in Archway on Monday on suspicion of murder and have since been released under investigation.
Murder detectives are searching ponds in Waterlow Park, Highgate, as well as a nearby flat on Bredgar Road.
Mr Duff's mother, Helen, said the family was "devastated" to hear he may have been killed.
"Robert's disappearance has always been forefront in our minds, and although we have always suspected that he may have come to some harm, there has always been the hope that he would return to us one day," she said.
"Our only wish now is that Robert is returned to us so we can grieve together."
The breakthrough in the case came after a renewed appeal in January.
A witness came forward and in February the case was passed to the Metropolitan Police's murder squad.
Det Ch Insp Luke Marks said Mr Duff was involved in a "spontaneous" fight with two men on the night he died.
He added that Mr Duff, from Kilburn, northwest London, was "well-known and likeable" and that there was no clear motive for someone to hurt him.
"I am making an appeal to the public once again, to come forward and help us complete the missing pieces of the puzzle," he added.
Mr Duff's friend Lana Purcell is also believed to have been murdered, but police are not linking the two cases.