A plane travelling between tourist destinations in Cambodia has gone missing and is thought to have crashed, aviation officials in the country say.
At least 20 people were believed to be on board, including 13 South Koreans, three Czechs and the Cambodian crew.
The plane was travelling between Siem Reap, home to the famous Angkor temple complex, and the coastal resort of Sihanoukville, officials said.
A search is under way to locate the missing PMT Air flight.
The plane disappeared from radar screens at around 1040 local time (0340GMT) - half an hour from its scheduled landing at Sihanoukville's recently re-opened airport.
Aviation officials said they believed the Russian-made AN-24 twin-propeller plane had come down in the hills of Kampot province, in Cambodia's south-west.
"We do not know the fate of the lost jet, but the authorities have sent helicopter search teams," Bun Ratha of Siem Reap International airport told Reuters news agency.
PMT Air has been operating flights between Siem Reap and Sihanoukville since January this year, the BBC's Guy De Launey in Phnom Penh says.
Tourist officials had hoped the service would encourage people visiting the Angkor temples to travel to the coastal town as well, he adds.
A PMT Air flight crashed on the runway in Ratanakiri province two years ago, but without serious injuries.