PHETCHABURI -- All 18 young people, 14 men and four women, suspected of attacking five Silpakorn University students at a dormitory on Feb 25, killing one and injuring two of them, have now surrendered to police, Cha-am police chief Pol Col Pakhin Siwamethakul said.
Earlier, police said 15 of the suspects were in custody. The three others, two woman and a man, gave themselves up to Cha-am police on Monday.
The attack occurred late on the night of Feb 25. The 18 suspects allegedly arrived at a dormitory near Silpakorn University's Phetchaburi Campus in Cha-am district in three cars and stormed into a room where five students lived.
Two of the five occupants managed to flee. The other three were assaulted.
One student, Teerapong Thitathan, 24, was stabbed in the head with a screwdriver. Seriously injured, he died at a hospital on March 2. The two other students were injured, one seriously.
Police Investigators learned that the attackers were looking for a student called "Off", who was in conflict over a girl student with Dechanon Moonmanee, one of the assailants. However, Off was not there when they arrived, and Teerapong, who died afterwards, was not involved in the dispute.
Using evidence from forensic examination and security camera footage, police obtained arrest warrants from Phetchaburi Court for 18 suspects.
One suspect, a man, was arrested at his home on March 1. Fourteen others, 12 men and two women, subsequently surrendered to police. They included Mr Dechanon, who was alleged to be the person who fatally stabbed Teerapong.
The 15 suspects were initially charged with premeditated murder and bodily assault using a weapon and released on bail.
The three others, two women and a man, gave themselves on Monday, Cha-am police said.
Pol Gen Chalermkiat Sriworakhan, a deputy police chief, was due to arrive at Cha-am police station later on Monday to follow up on the case.