Harrowing footage shows stranded revellers sitting on the window ledges of a casino in Cambodia where a fire killed at least 10 people.

The blaze tore through the inside of the sprawling Grand Diamond City building in Poipet province shortly after midnight local time.

Dozens of fire crews including teams from neighboring Thailand, a short drive across the border, raced to the inferno.

It reportedly took more than six hours to bring it under control and the building collapsed. The fire was still ongoing this morning at 8am local time.

Many revellers were stranded on top of the building and jumped to their deaths. At least 10 people have been killed with more than 50 believed to have been trapped inside.

Graphic footage showed people plunging from windows and the roof of the building to escape the flames.

Casinos are legal in Cambodia and popular with tourists from Thailand and China, where both countries ban gambling.