A cafe owner who tried to help the two Newcastle University students stabbed to death while on a medical placement in Borneo described the scene of their killings as one he will "never forget".
Local police said four men arrested in relation to the murders of Neil Dalton and Aidan Brunger in the early hours of Wednesday morning had admitted the crime.
The owner of a bistro in the Jalan Padungan area of Kuching in Sarawak province, in the west of the Malaysian part of Borneo where the attack happened, said he saw one of the alleged killers calmly walk away after the incident, the Mirror reported.
Avinash Ran told the newspaper: "He looked right into my eyes when he saw me and slowly walked around the side of the car and got inside the passenger seat.
"He was trying to act all cool in front of his friends, but his eyes were wide like two moons. I don't know if he was on drugs, but he wasn't acting normally.
"Nobody acts like that after stabbing someone. It was like it was nothing to him."
Mr Ran said he and another waiter tried to help Mr Dalton and Mr Brunger, both aged 22, but they died before an ambulance arrived 30 minutes later.
"I will never forget it, not as long as I live," he told the paper.
Deputy police commissioner Chai Khin Chung said yesterday that police had completed their inquiry, as the men had confessed, and they would now be passing on their evidence for prosecution.
"We have finished our investigation, the crime has been solved," he said.
"The suspects have been apprehended and they have admitted the crime. We have recovered the weapons from the crime.
"We are waiting for the corpses in the hospital mortuary to have the post-mortem carried out. We have all the major evidence in our hands which we will send to the prosecution."
He said the two students had got into an argument with the men on the table next to them in the bar and after leaving on foot, they were followed by car and then attacked from behind.
He added that the tragedy was very unusual for the city as it is "always very peaceful".
Malaysia's The Star newspaper has reported the main suspect is a 23-year-old fishmonger, one a 29-year-old mechanic, the others 19 and 35 and both unemployed. Two are said to have previous convictions for drugs and armed robbery.
It has been reported that two Irish medical students were assaulted just days before the stabbings.
The hospital where Mr Dalton and Mr Brunger had been working is providing counselling to other students since the tragedy.
Sawatar Hospital medical director Dr Chin Zin Hing said the deaths of the two men, who finished their elective with the hospital at the end of last month, were "very sad".
He said: "We are trying to provide counselling for the students here. We currently have about 20 British elective students."
Newcastle University said two members of staff had been sent out to Kuching to offer support to the students still out there and to help the authorities.
Professor Calvert said: "We have been in touch with the students who are still in Kuching, in constant touch really, overnight there have been emails going back and forward to try and offer what support we could until our staff could get there.
"We now have two members of staff who have arrived in Kuching, they have met up with the students and are trying to smooth the way with the authorities to make things as easy as possible so they can do what has to be done and then get back home again.
"Of course they're very, very upset, medical students are a close community anyway and they were out there with friends and colleagues from their course and it's such a tragic thing to have happened.
"They're very upset but we're confident the people we have out there are offering them every support and just hope we can get them back soon."