Monday was the eighth day since the murders but police had failed to find solid clues or the possible motive.
The officials were waiting result of DNA test of latest three suspects; two Thai and one migrant who looks like a man appeared in close circuit television earlier.
Anyway, police have confirmed that two weapons were used to kill the pair – which led them to believe they are hunting at least two people.
The body of Hannah Witheridge, the young female backpacker slain on the island, meanwhile, left Bangkok for her home country. Her family said in a statement: “We can confirm that we have now returned to the UK with our beautiful Hannah. As a family we feel enormous relief to have Hannah back at home where she belongs.”