BANGKOK (Reuters) - Human Rights Watch on Friday urged Thai authorities to drop legal cases against 12 people arrested over Facebook posts they shared about a British tourist’s complaint that she had been raped on a holiday island.

Police arrested the 12 Thai Facebook users this week for violating a cyber-crime law, in connection with their posts about what police have deemed to be an untrue complaint of rape.

Police had been investigating an accusation by a 19-year-old British tourist who said she had been raped while on holiday on the island of Koh Tao in June.

A lawyer for the 12, Winyat Chatmontree, said they had been arrested under the Computer Crime Act. They face up to five years in prison and fines for spreading false information and damaging national security, if found guilty.

Thailand is sensitive about how it is perceived abroad, particularly because of any impact on tourism which is an important driver of the economy.

Arrest warrants have also been issued for the British publisher of the online newspaper Samui Times, and the Thai-American administrator of the CSI LA Facebook page, for reporting the story and raising concern about the standard of the police work.

Brad Adams, Asia director at Human Rights Watch, said the police appeared to be using computer-related crime charges against anyone who questioned their investigation of the case.

“The authorities should immediately drop these bogus charges,” Adams said in a statement.

The British tourist, whose identity has not been revealed, reported to police in June that she was robbed on the island. But upon her return to Britain, she told police there that she had also been raped.

Media have reported that the woman said she was turned away by Thai police when she tried to report the rape.

Police deny this and say their investigation determined her complaint of rape was not true.

“The 12 arrested shared information ... which affects Thailand’s image, because according to our investigation the incident alleged by the British tourist never took place,” Napah Senatip, deputy inspector of Koh Tao police, told Reuters.

Concerns over safety on Koh Tao were heightened after it made headlines in 2014 when the bodies of British backpackers Hannah Witheridge, 23, and David Miller, 24, were found on a beach.

They had been bludgeoned to death.

Two Myanmar migrant workers were found guilty in 2015 of killing the pair. They have been sentenced to death.