Rescue workers close bags containing the bodies of two British tourists found dead on a beach on Koh Tao island this week. Photo: Reuters

Thailand’s seemingly idyllic island resorts can spell danger to tourists, as the brutal murder of two British travellers this week illustrates only too clearly.

Glowing travel brochure descriptions of tranquil, turquoise waters, sandy beaches and jungle walks hide the fact that crime is a constant factor in this part of Southeast Asia.

The bodies of Hannah Witheridge, 23, and David Miller, 24, were found with severe head wounds on the island of Koh Tao on Monday.

According to the Foreign and Commonwealth Office (FCO), as many as 11 Britons have been murdered in Thailand since 2009.

In a 2012/13 New Year’s Eve party Londoner Stephen Ashton, 22, was killed in a bar on Haad Rin beach on the Thai island of Koh Phangan – a resort where the FCO warns travellers to beware “vicious, unprovoked attacks by gangs”.

The FCO says such attacks are particularly common around the time of Full Moon parties and generally occur late at night near bars in Haad Rin.

British visitors are also warned that violent assaults and robberies have been reported in the resort town of Chaweng in Koh Samui.

Attacks have also occurred in other Thai tourist districts including Chiang Mai, Pattaya and Krabi.

In July last year an American was stabbed to death and his son seriously injured in an attack in a bar in Krabi. On crime generally, the FCO warns visitors to beware scams, pickpockets, bag-snatchers and credit card fraud. Just a few weeks ago, the FCO published comprehensive, country-by-country lists of places where Britons needed consular assistance in the 12 months ending March 2014.

The list also showed where Britons have been victims of crime.

Taking into account the number of visits made to a country as well as the number of Brits living there, Thailand was second only to the Philippines for visitors needing the most help.

In 2013/14, Britons made over 906,000 visits to Thailand. There were 1,164 incidents of consular assistance, including 11 cases of rape, six of assault and 267 instances of Britons in hospital. There were also 362 deaths in 2013/14.

The latest murder is a further setback for Thailand’s tourism industry, which is still recovering from the military coup that took place in May this year.

For a time, tourists had to obey a strict night curfew that was lifted after a few weeks. The FCO warns Britons that it is illegal to criticise the coup and that visitors “should be wary of making political statements in public”.