The Ilyushin Il-76 cargo plane went down as it attempted to land at the Osman Digna Air Base in the Red Sea city of Port Sudan after experiencing a "technical malfunction", according to a military source, who spoke on condition of anonymity because they are not authorised to brief the media.

"All members of the aircraft's crew were killed in the crash," another military source said, also anonymously.

The Sudanese army has not disclosed how many personnel were on board and no official casualty figures have been released.

The Il-76, a Soviet-designed heavy transport aircraft, has long served as a workhorse of the military and is used to move supplies and personnel across frontlines.

The incident came as Sudan remains engulfed in one of the world's worst humanitarian crises.

Since April 2023, the army and the paramilitary Rapid Support Forces (RSF) have been locked in a brutal power struggle that has killed tens of thousands of people and displaced nearly 12 million.

Millions more have been left in need of humanitarian assistance as fighting continues across multiple fronts.