According to AFP, Thai police said they carried out a DNA test late Sunday (September 21) on a speedboat driver arrested for a drug offense, as they extended their hunt for the assailant(s) of double-homicide of British couple.
The investigation into the grisly murder has so come up empty-handed, with police under increasing pressure to identify killers.
The battered bodies of Britons David Miller, 24, and Hannah Witheridge, 23, were found on a beach on Koh Tao island a week ago.
A 23-year-old Thai suspect was arrested Sunday for an unspecified drug offense, according to Kiattipong Khawsamang of Surat Thani provincial police.
"We are waiting for the (result) of his DNA test...It is not clear if he is a suspect yet, Kiattipong told AFP, adding that the man drives a speedboat between Koh Tao and the nearby island of Koh Samui.
Police are also searching for two friends of the driver, Kiattipong said, without giving further details.
COMMENT: Deputy National Police chief Somyot Poompanmoung told AFP the man was being questioned, but had not been arrested or charged in connection with the homicides.
Earlier Somyot said the DNA of two Asian men was found at the crime scene and had been sent to Singapore for expedited forensic analysis.
Forensic experts in Bangkok discovered traces of semen at the scene, but could not find a DNA match with twelve suspects.
Critics have said police chased the wrong leads, failed to lock down the island and poorly secured the crime scene in the hours after the badly beaten bodies were found early last Monday.