Thai police believe at least three "attackers" were involved in the vicious murders of two British backpackers whose semi-naked bodies were found on a tourist idyll this week.
David Miller and Hannah Witheridge, who had met on Koh Tao in the Gulf of Thailand, are thought to have been murdered at around 4.30am after leaving a beachside bar on the island together.
Evidence gathered from witnesses and the crime scene, including DNA traces found on cigarette butts left near the bodies, now suggests the involvement of more than two people, police say.
"From the available evidence, we believe that there were more than two attackers," Police Lieutenant General Panya Mamen was quoted as saying by Thailand's The Nation newspaper yesterday.
The parents of 23-year-old Ms Witheridge, a speech therapist from Great Yarmouth, arrived in Bangkok on Thursday to accompany investigations. It is not clear if relations of Mr Miller, a 24-year-old University of Leeds engineering graduate, will also travel to Thailand.
Police have been accused of bungling initial investigations after failing to properly seal off the stretch of beach where the murders took place and apparently taking days to conduct a thorough forensic examination of the crime scene and the surrounding area, including the victims' rooms.
Bloodied bandages that had been left outside Mr Miller's hotel room, which was just a few metres from the crime scene, were only examined and removed by police on Wednesday having spent more than 48 hours exposed to the elements in a dustbin.
At first police on Koh Tao claimed an arrest was imminent and said they had identified a British man as their prime suspect. However, those hopes came to nothing and police now appear to have no firm suspects.
Two British friends of Mr Miller's were stopped from leaving the country and questioned in Bangkok but they were allowed to return to the UK on Thursday after being ruled out.
Police General Jarumporn Suramanee, Thailand's assistant national police chief, denied his officers had "messed up".
Forensic teams had performed a thorough examination of the crime scene on the day of the murder, he claimed during a visit to Koh Tao. "We were here from the first day."
The Metropolitan Police's help in solving the case would be "welcome", the police chief added. In the early hours of yesterday a reconstruction of the crime was held on Koh Tao's Sairee beach, where the victims' spent their final hours. Officers found "evidence that is quite useful to the investigation," according to Jarumporn Suramanee, without elaborating.
Officers were also understood to be searching areas of forest on the east side of the island. Police divers were seen searching an area of coast near the murder scene for a metal object thought to have been used as a second murder weapon.
Police have also been questioning and taking DNA samples from a number of Burmese workers on the island, sparking anger among many members of Koh Tao's large expat community.
Many believe investigators are unfairly targeting foreigners, and particularly the Burmese, and are not properly investigating potential Thai suspects. "It's so absurd. It's horrific," one European business owner said. "If something happens it is never the Thais. They always blame the Burmese or the Westerners."
Police Lieutenant General Panya Mamen told The Nation: "We still believe we will bring the attackers to justice."
"Police have collected a lot of evidence and interviewed many people, and this should help us find the culprits. There is a lot of evidential information that we cannot reveal", he added.
(© Daily Telegraph London)