Gardaí last night began their second murder investigation in four days after the body of a Lithuanian man was found at a house in Clones, Co Monaghan.
It is believed the man had become involved in an altercation early yesterday morning.
He was found dead in a flat on Roslea Road at around 9.15am. He had sustained a number of stab wounds to his upper body.
Gardaí were called to the house at around 8am when a disturbance was reported as a late night party continued into the morning.
The man was alive when gardaí left the scene. However, they were called back for a second time at 9.15am at which point they found the dead 21-year-old. The scene was sealed off and the Garda Technical Bureau carried out a forensic examination.
The remains were removed to Cavan General Hospital where State Pathologist Prof Marie Cassidy was carrying out a postmortem last night.
Detectives from the National Bureau of Criminal Investigation travelled to the town yesterday to support local gardaí from Clones and Monaghan town in their investigation.
Garda sources last night said while the inquiry was at an early stage, they believed the dead man had been killed by people known to him, who were also from Lithuania.
Detectives were working on the theory that a number of people had fled the flat in a vehicle after the man was attacked and before gardaí returned for the second time.
They believe the men may have fled over the Border into Northern Ireland. The dead man had been living in Co Fermanagh.
Yesterday's murder was the second in four days in the Republic.
It followed the stabbing to death of well-known Co Waterford horse trainer Dick Forristal on Thursday during an apparent botched robbery at his home at Carrigavantry stud near Tramore.
Two men have been before the courts in relation to Mr Forristal's death. One has been charged with murder and the other with burglary.
Quarterly crime figures released by the Department of Justice last week revealed the number of killings in the State in the first six months of this year had risen by 35 per cent.
Minister for Justice Michael McDowell has expressed his concern at the rise in the number of violent deaths, linked to gangland crime.
These rose from 17 in the first six months of 2004 to 23 in the first six months of this year.
