A 45-year-old was last night still being held by police on suspicion of murder following the death of a man, believed to be his twin brother, in a Co Armagh flat.
The body of the dead man was discovered in the Johnston Allen block of flats on Victoria Street in Lurgan on Sunday afternoon.
Police were yesterday waiting for the results of forensic and postmortem tests.
It is understood that the brothers are originally from Lithuania.
The death happened in the same complex where 31-year-old Laura Marshall was found dead in April 2016.
Sinn Fein councillor Liam Mackle called on people to "come forward with any information at all to police".
"It is unfortunate and tragic incident," he said.
