GARDAÍ investigating the murder of a 24-year-old Japanese man during a series of random attacks in Dundalk have said terrorism is one line of inquiry.
An 18-year-old Egyptian man has been arrested on suspicion of the knife murder and subsequent assaults on two other men - one with a knife and one with a fence pole.
Gardaí have not established a definite motive for the violent spree in the Avenue Road area around 9am yesterday but Chief Superintendent Christy Mangan said a potential terror link was being investigated.
"A terror attack is a line of inquiry," he said.
"It is certainly a line that we would look at. We will endeavour to establish the suspect's background, who they are and where they have come from and why are they here.
"Those are the very important questions we are endeavouring to ask and answer. And as to why the attacks took place, why an innocent bystander going about their work would be attacked in the middle of Dundalk in the morning slightly before 9am."
Mr Mangan declined to confirm whether a potential mental health link was another line of inquiry.
He said the suspect had come into contact with gardaí on January 1 when inquiries about his immigration status were conducted.
The senior officer said he believed the teenager was seeking asylum in the Republic.
The series of attacks started when the Japanese man was fatally stabbed on Avenue Road shortly before 9am.
An Irishman was stabbed a short time later on nearby Coes Road. At 9.40am gardaí received a report that another Irishman was attacked with a fence pole at Seatown Place. Neither of them sustained serious injuries.
The suspect was arrested at around 9.45am on Inner Relief Road in Dundalk. He has been detained at Dundalk Garda Station.
Mr Mangan said he believed the perpetrator was on foot and the victims were selected at random.
"There is nothing to suggest whatsoever that any of these people involved in the attack and the subsequent assaults were known to each other," he said.
"It would certainly appear to be random and unprovoked."
He said there was no evidence that anyone assisted the attacker.
Mr Mangan said gardaí were making efforts to contact the dead man's relatives.
"It is going to be very, very hard for the family," he said.
"They have someone over here working and the next thing they get attacked and killed in a foreign country."
He said the investigation would have an international dimension and gardaí would be liaising with the authorities in Egypt.
Councillor Ruairi O Murchu lives close to the scene of the attack in Avenue Road.
He said there was major concern among local people.
"The community is in shock," said the Sinn Féin representative.
"Our thoughts are with the family of the person killed and those that have been injured."
