Both crew members on board the plane were killed in the crash [Reuters]

A cargo plane belonging to United Parcel Service (UPS), a US-based delivery company, has crashed near the United Arab Emirates city of Dubai.

The two crew members were killed as the plane went down in an unpopulated desert area of a UAE military base, officials said.

The accident occurred just after the plane took off from Dubai airport on Friday as the crew attempted to make an emergency landing.

There were reports that the aircraft's cockpit had caught fire before the crash.

Saif al-Suwaidi, the general manager of the country's civil aviation authority, told local media agencies: "The pilot reported fire and smoke in the cockpit and was instructed to return to Dubai.

"After failing to land at the airport, the plane disappeared from radar screens and was found later [at the crash site]."

The official news agency Wam, quoting aviation officials, reported that the "bodies of two pilots'' had been found at the scene.

Al Jazeera's Dan Nolan, reporting from just outside the crash site, said: "I can see a large plume of thick smoke in the distance, there is certainly a big fire. 

"The Boeing 747 was it was on its way to Cologne in Germany, but we understand there was problem with the plane."

Ismail al-Baroushi, a spokesman for the aviation authority, said an investigation into the accident was under way, but it was "too early to speculate" on the cause of the crash.

A spokesman for the US transportation safety board has said the agency will send a team of experts to Dubai to assist with the investigation.

Source: Al Jazeera and agencies