The data and voice recorders from a Boeing 747-400 plane operated by U.S. parcel delivery firm UPS that crashed in Dubai this month have been sent to the United States for analysis, the UAE state news agency said.

Two crew members died when the cargo plane, which was en route to Cologne, Germany, crashed in a military compound near Dubai's airport on Sept. 3 after the pilot reported fire and smoke in the cockpit.

The United Arab Emirates civil aviation authority sent the cargo plane's "black boxes" -- a flight data recorder and cockpit voice recorder -- to the U.S. National Transportation Safety Board's (NTSB) last week, state news agency WAM said.

The NTSB's initial findings confirmed there had been a fire warning on the plane followed by smoke in the cockpit around half an hour after takeoff, which led to the crew encountering visibility and communication problems.

Air traffic control in Bahrain had offered the crew to land in Doha, Qatar, but they decided instead to return to Dubai, WAM reported.

The UAE's civil aviation authority was still collecting evidence from the crash site, WAM said.

The Boeing 747 is a backbone of the world's freight industry, transporting about half the cargo carried in dedicated freight planes, according to manufacturer Boeing. (Reuters)