A military cargo plane crashed in Democratic Republic of Congo's capital Kinshasa on Saturday, killing its 12 crew members, the defence minister said.

"I confirm that a military aircraft crashed this morning," said Defence Minister Crispin Atama Tabe. "All 12 members of the crew died."

According to an army officer who witnessed the incident, the cargo plane caught fire shortly after taking off from Kinshasa's N'djili Airport and crashed in a nearby reserve controlled by the military's elite Republican Guard units.

The officer, who asked not to be named, said that there were both Congolese and foreigners among the dead. An agent at Congo's aviation agency, also speaking on condition of anonymity, said the plane was an Antonov 12 destined for the eastern city of Bukavu.

It was not immediately clear if anyone was killed or injured on the ground. Soldiers prevented journalists from approaching the crash site, but billowing smoke could be seen from several kilometres away, a Reuters witness said.

Air accidents are relatively frequent in Congo due to lax safety standards. All Congolese commercial carriers are banned from operating in the European Union.