A 40-year-old man is today being questioned by police in Belfast about the disappearance and suspected murder of a former right-hand man of jailed loyalist Johnny Adair.
The man, arrested in north Belfast, is being questioned about the whereabouts of 21-year-old Mr Alan McCullough who has been missing since he was driven away from his Shankill Road home by two men last Wednesday.
Police searching for Mr McCullough said they believed he might have been murdered.
He was among the Ulster Defence Association's C Company forced to flee Northern Ireland under threat of death during the UDA feud earlier this year.
However, he returned to his home in the Shankill Road area within the last fortnight, police have revealed.
Detective Chief Superintendent Will Kerr, who is leading the hunt for the missing man, said police believed there was a paramilitary connection to the disappearance.
"We are concerned about Alan, at this stage we have a belief that Alan may have been murdered".
As detectives continued a major search operation for him, he added: "We are resourcing it as a murder inquiry".
A two-day search by police divers of a reservoir at Waterworks Park in north Belfast and of a boat at Carrickfergus, Co Antrim have failed to provide clues.
Four people died during the UDA feud which saw Johnny 'Mad Dog' Adair returned to jail when his early released parole was ended for a second time when he tried to wrest control of the UDA from those in charge.
After be was back behind bars the UDA leadership warned his C Company followers to get out.
They fled on an overnight ferry to Scotland and scattered across Scotland and England.
Adair's wife Gina was among those who, together with McCullough, went into exile. They were warned that if they ever returned they would be shot dead.
In April there was a gun attack on the Bolton house where Gina Adair had taken refuge.
McCullough is understood to have made contact with the UDA and pleaded to be allowed to return home in safety.
Less than two weeks after doing so he vanished.
PA