PHNOM PENH: A real estate tycoon was among three Russian men arrested and charged in Cambodia over accusations they threatened and locked up the crew of a boat at knifepoint, an official said Friday.

Sergei Polonsky, 40, and two other Russians identified only as Karachinsky, 24, and Baglay, 25, were detained by authorities in southwestern Sihanoukville on Monday, national military police spokesman Kheng Tito told AFP.

The trio allegedly used a knife to threaten a crew of six boatmen on Sunday while they were bringing the Russians back to shore from a nearby island, he said.

The victims told military police they were locked in the boat's cabin and bathroom and then forced by the Russians to jump into the sea, Kheng Tito said. It was unclear what prompted the alleged offenses.

Prosecutor Huot Vicheth at Sihanoukville court said the men had been charged with intentional violence and illegal detention. There was no immediate comment from the accused.

Polonsky, who is believed to have business interests in Cambodia, is an outspoken real estate tycoon whose extravagant behaviour and racy business slogans in Russia have repeatedly raised eyebrows in the past.

The former head of the Mirax Group real estate firm was punched by Russian billionaire and former KGB agent Alexander Lebedev during an argument on a Russian talk show in September 2011.

Polonsky's business nosedived after the onset of the 2008 global financial crisis, forcing him to abandon work on Moscow's Federation Tower, which he hoped would become the tallest building in Europe.