A 24-year-old man has died and two others were wounded in a stabbing incident in Dundalk.
The first incident happened on Avenue Road at around 9am, where the victim, who was from Japan and had been living in Ireland for the past year, was attacked on the street and stabbed in the back.
He died at the scene.
His body was removed to Our Lady of Lourdes Hospital where a post-mortem examination is being carried out.
Gardaí said that a call was received from ambulance control to Drogheda Garda Station at 9am reporting that a man had been found unresponsive at Avenue Road.
Gardaí arrived at the scene at 9.07am.
At 9.32am another call was received regarding another incident at Coes Road in Dundalk and a further call was received at 9.40am about an incident at Seatown Place,.
Two men had been attacked with an iron bar at those locations and were taken to hospital.
Their injuries are not believed to be life-threatening.
Chief Superintendent Christy Mangan said that a member of the force later observed a person carrying a fencing post and acting in a suspicious manner.
The garda called for assistance and the attacker was disarmed and arrested.
Initial reports suggested the man was from Syria, however further investigations suggest that he is 18-years-old and from Egypt. It is believed that he was carrying at least two knives along with the fencing post.
Initial investigations indicate that he may have applied to remain in the UK, but may have been refused and entered Ireland following the refusal.
At a press briefing this afternoon, Chief Supt Mangan confirmed that the 18-year-old had been in contact with gardaí from the Immigration Section two days ago in relation to a possible application for residency in Ireland, and there was no indication then of any involvement on his part in criminality.
He has been arrested on suspicion of murder and is being detained at Dundalk Garda Station where he can be questioned for up to 24 hours.
Gardaí say they have yet to establish a motive for the attack, but one line of inquiry is a possible link to terrorism.
Chief Supt Mangan said the attack appeared to be random and unprovoked and gardaí have so far found nothing to suggest that the victims knew each other.
He said gardaí are satisfied at this time that the suspect acted alone and that he was in Dundalk on 1 January.
Part of the investigation, he said, will be to establish why the suspect was in Dundalk and who he was associating with.
He added that gardaí will be speaking to Egyptian authorities regarding the young man's movements.
The three scenes have been preserved pending the arrival of the State Pathologist and the Garda Technical Bureau.
An appeal for information has been issued and anyone who was in the Avenue Road area before 9am, the Coes Road or Seatown Place areas or the Inner Relief Road between 8.30am and 9.40am are asked to contact Dundalk Garda Station on 042-9388471 or the Garda Confidential Line on 1800 666 111.
Chief Superintendent Mangan said no further details on the victim will be released until his family have been informed.
He said the man was on his way to work when he was attacked, adding, "it's very hard on the family when someone is walking to work and they get attacked and killed in a foreign country".