The British travellers were named as Hannah Witheridge, 23, and David Miller, 24.
Hannah, from Great Yarmouth, had recently graduated from the University of East Anglia. David Miller is believed to be from Jersey and was travelling with friends.
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The pair were believed to be returning to their accommodation after leaving a bar on the island of Koh Tao.
Their bodies were found after what police described as a ‘gruesome’ attack, which left both victims with serious head and facial injuries.
The murder weapon is reportedly believed to be a gardening hoe, which was found nearby to the crime scene.
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Police spokesman Major General Kiattipong Khawsamang said in a statement: "They went out to a bar and left together after 1am (Monday), according to closed circuit TV camera footage.
"This should not have happened in Thailand. It will affect our image in the eyes of international countries."
"We are focusing on migrant workers because of the surrounding witnesses and evidence, including the video footage.
"We are sweeping hotels, bars, businesses and residences of migrant workers on the beach to find the suspect."
"This morning we surrounded three locations, including the residences of migrant workers, to search and collect DNA."
According to reports, police are seeking an ‘Asian’ man who was spotted on CCTV around the area of crime scene around the same time the murders occurred.
Police Colonel Somsak Noorod told a UK newspaper: “The man walked back and forth in the area sometimes quite hurriedly during the period it is estimated the victims died, between 2am and 4am.
“We are in the process of trying to identify this man.”
Police are also looking for David Miller’s friend who is believed to have already left the island following the shocking murders, though his name has not been released to press but ‘circulated’, though he is not said to be a suspect.
Mr Miller’s girlfriend Jessy Howarth paid tribute to him on social media, writing: “My best friend and the love of my life. We were meant to have so much more time together but I'll continue loving you everyday forever.”
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