Thailand police say they have narrowed down the list of suspects in the murder last week of two British tourists on the island of Koh Tao, media reports Monday said.
David Miller, 24, and Hannah Witheridge, 23, were beaten to death and their bodies found semi-naked Sep 15 near a beachside bungalow on Koh Tao island, the Bangkok Post reported.
Witheridge's skirt was hiked up to her waist and her T-shirt pulled up. She was raped and had a huge injury on her face.
Miller had an injury to the back of his head.
A bloodstained hoe (a hand tool used for gardening) was found at the scene, police added.
A senior police official said detectives were waiting for the results of DNA tests on samples collected from 30 people.
They are either workers or staff of hotels and restaurants located near the crime scene on Sairee beach.
He said detectives were also focusing on footprints found near a cigarette butt left on the beach where the bodies were found.
The the reward for information on the culprits was also increased to 700,000 baht ($21,742).
The couple had arrived on the island Aug 25.
According to witnesses, Miller and Witheridge were seen partying on the beach with a group of about six people the night they were murdered.
Koh Tao, home to white sand beaches and azure waters, draws hordes of foreign backpackers to its "full moon" parties.
