Thai police have questioned three Myanmar (Burmese) men over the murder of two British tourists on the southern resort island of Koh Tao, as their bodies were due to arrive in Bangkok for forensic tests.

David Miller, 24, and Hannah Witheridge, 23, were found naked and beaten to death early Monday near a beachside bungalow on the island, a diving hot-spot near Koh Phangan in the Gulf of Thailand.

A bloodied hoe was discovered 35 metres from the murder scene.

• $1.2m payout after ‘feral’ class
• US military to fight Ebola
• Aussie dies on Canadian glacier

“Three male Myanmar migrant workers are under police detention for investigation,” said southern regional police commander Panya Maman, without providing any further details.
A second officer said police were not looking for a British man who had travelled with Miller, contrary to UK media reports.

“All of the British nationals are now on their way home,” said provincial police chief Kiattipong Khawsamang, adding they had been “cleared” as suspects.

Neither officer was able to confirm Thai television reports that police had seized an iPhone and blood-stained jeans after raiding rooms used by the Myanmar suspects.

Thai authorities frequently accuse migrants from Myanmar and Cambodia of committing crimes in the kingdom, where they make up a vast, poorly-paid and low-status workforce.

The bodies of the victims, who arrived in Thailand on August 25, are being driven the 500 kilometres from southern Surat Thai province and are due in Bangkok later Tuesday for forensic tests.

Koh Tao, home to stunning white sand beaches and azure waters, is popular with divers but is smaller and more laid-back than neighbouring Koh Phangan – which draws hordes of backpackers to its hedonistic “full moon” party.

On Tuesday, Thai junta chief and prime minister Prayut Chan-ocha appeared to call into question the victims’ conduct in addition to the perpetrators of the attack.

“We have to look into the behaviour of the other party too because this kind of incident should not happen to anybody and it has affected our image,” he told reporters, referring to the two tourists.

Speaking a few hours later he said Thai authorities must tell “tourists when the safe times are to be outside, we have to help them understand.”

Police earlier said the pair had been seen partying at a local bar just hours before they died.

The murders are likely to heap more misery on Thailand’s lucrative tourism industry, which has been battered in recent months after a prolonged political crisis ended in a coup.

The army swiftly blanketed the country with a curfew and strict martial law, frightening off visitors.

Although the curfew was soon lifted from key tourist hotspots, visitor numbers have yet to rebound and martial law remains in place.

Military leaders have vowed to restore the nation’s reputation as the “Land of Smiles” with a clean-up targeting tourist resorts after a series of complaints about scams, assaults and even police extortion.

Britain says Thailand is the country where its citizens are second most likely to require consular assistance if they visit, behind the Philippines.

There were 389 deaths of British nationals in Thailand in the year to March 2013 – about one for every 2400 British visitors or residents – although that figure includes natural causes.