SYDNEY, Aug 12 (Reuters) - A helicopter crashed into the roof of a hotel in the popular northern Australian tourist town of Cairns, killing the pilot and forcing the evacuation of hundreds of guests, authorities said on Monday.

Emergency crews were called at about 2 a.m. on Monday (1600 GMT on Sunday) after a twin-engine helicopter collided with the hotel roof, causing a fire on top of the building and triggering evacuations, Queensland state police said in a statement.

Police said forensic investigations were underway to formally identify the pilot. He was declared dead at the scene.

"There were no injuries sustained by people on the ground," the police statement said.

The crash occurred at Hilton's (HLT.N), opens new tab Double Tree Hotel in the city of Cairns, a major gateway to Australia's Great Barrier Reef, Australian media reported.

Two of the helicopter's rotor blades came off and one landed in the hotel pool, media reports said.

The forensic crash unit will work with Australia's transport safety regulator to prepare an accident report, police said.