Cambodia's ambassador to Thailand has flown from Bangkok to monitor the investigation of five Cambodian fishermen accused of the rape and assault of French tourists on the southern Thai island of Koh Kut, officials confirmed yesterday.

The five men known only as Thi, 20; Bot Man, 20; Yim, 25; Pai, 22; and Jern, 25, were arrested on Sunday for their role in the alleged rape of two French women and the beating of their two male companions.

All have already confessed, Thai police Major General Nopparat Rinthaphol said, adding that “police have already brought them to do a re-enactment”.

That re-enactment took place yesterday as Thai authorities took the five men back to the beach and forced them to walk through Saturday night’s events for cameras, a ritual also routinely employed by Cambodian police after major arrests.

The scene quickly turned into a spectacle as police were forced to cordon off an angry mob that tried to attack the men. One protester broke through the police line and punched one of the suspects in the face.

Dy Thehoya, head of the migrant project at local rights group Central, yesterday described the reports of the men being paraded in front of locals and police as “concerning”.

“I am concerned that the five Cambodians should have a lawyer to protect their rights,” he said.

He said he was still making enquiries with his counterparts in Thailand to understand the status of the men, but things had been made tougher for civil society since the military seized power in Thailand in 2014.

“The Thai junta has not made it easy for NGOs to follow up or take action,” he said.

According to Thai police, the incident took place on Saturday night, when the fishermen, docked about 300 metres from the shore, are alleged to have swum to the resort beach to buy alcohol.

Police say the tourists encountered two of the suspects along the road about 1 kilometre from their resort and began a conversation with them.

When the French nationals tried to leave, three other men are alleged to have come out of nearby bushes and grabbed the women.

The male tourists, identified as Thomas Buiron, 30, and Edbri Ronain Rene, 29, tried to retaliate, but were attacked with sticks and a knife.

According to Thai authorities, both women, one aged 57 and the other 28, were raped and assaulted.

Cambodian Foreign Ministry spokesman Chum Sounry said yesterday that the Cambodian ambassador to Thailand, Eat Sophea, had accompanied Thai authorities to the island to investigate the case, “to make sure that it did happen or whether it is [a true] allegation or not”.

Authorities were not yet aware of the background of the five men, he said, adding that if the men were charged, the government would provide a lawyer for them.

Sounry described the case as “sensitive”, and said it had potential to damage Cambodia’s reputation, but cautioned, “we have to wait to see whether it is like the reports or not”.

He said that more details of the investigation would be available today.

Thai authorities have come under fire for their handling of the case of two Burmese men, who were last year sentenced to death in Thailand for the murder of two UK tourists in 2014.

Questions have been raised about whether police poorly managed the crime scene and about their evidence-collection techniques.

Additional reporting by Daniel de Carteret, the Bangkok Post and AFP