Oil companies say a helicopter carrying contractors has crashed into an oil-drilling platform off the coast of Dubai, killing seven people.

Petrofac and Dubai Petroleum say the helicopter operated by Dubai-based Aerogulf Services struck the deck of the Maersk rig during takeoff at about 8:20 p.m. Wednesday. A fire then broke out aboard the rig, which is located in the Rashid field about 40 miles offshore.

"The aircraft then broke up and fell into the sea," Petrofac, the operator of Dubai government's offshore oilfields, Reuters reports it said in a statement. It declined to say how much the oilfield produces.

"Immediately following the incident, a fire broke out on the main deck of the drilling rig which was quickly contained and extinguished... All operations on the Rashid field have been suspended and the platform and drilling rig have been secured."

The helicopter was carrying an American, a Briton, a Pakistani, a Filipino, a Venezuelan and two Indians, none of whom survived, Reuters reported. Two were crew members and fiver were contractors.

The cause of the crash was not immediately known.

"The General Civil Aviation Authority of the United Arab Emirates immediately set up an investigation team to find out the cause of the aircraft crash," it said in a statement.

The companies say the victims' families are being informed.

Click here to read the Reuters report.

The Associated Press contributed to this report.