The brother of a British backpacker missing in Cambodia says he feels let down by the UK government as the search for her continues.
Amelia Bambridge, 21, from Worthing, Sussex, was last seen at a beach party on the island of Koh Rong on Wednesday.
Her brother Harry, who served as a paratrooper for four years, joined the search on Sunday but said the language barrier was causing problem.
"There is nothing making sense and something's not quite right," he said.
On the night Ms Bambridge disappeared, she had been with friends she had met at the hostel and they had gone to Police Beach - named after its proximity to a disused police station.
Friends reported her "out-of-character" disappearance after she did not return and her belongings were found on a beach.
Mr Bambridge said: "We were up at 06:00 and met with Cambodian police. We spent all day searching and wading through the jungle.
"We don't seem to be making any headway. We have got no leads to go off. I left my emotions on the plane. All I'm doing is concentrating on finding my sister."
Mr Bambridge was critical of the British government and said he has had to turn detective in a bid to find his sister.
Major general Chuon Narin, police chief of Sihanoukville province, said divers, police, navy personnel, local volunteers and foreigners were taking part in the searches.
"As of now, the searchers have no news about her whereabouts and they have expanded the area they are searching to make sure all possible sites are checked," he told AP news agency.
"I can't say whether [Ms] Bambridge was killed or got lost in the island's jungle."
Mr Bambridge added: "We have a 20-minute window where we can place her and then she just disappears.
"For me something's not right. We have had divers out searching the water. The water is shallow so the chances of her drowning are quite slim.
"There is a breakdown in communication with the language barrier. I believe the police are doing the best they can.
"I have had zero involvement from the UK government. Where's the support?"
The Foreign and Commonwealth Office said: "We are assisting the family of a British woman who has been reported missing in Cambodia and are in close contact with the Cambodian police."