Fighting between the two rival factions of the Sudanese military has spread to the Red Sea city of Port Sudan for the first time in five months of conflict.
Sudanese soldiers exchanged fire with members of a tribal militia group which calls itself the Forces of the Eastern Sudan Parties and Movements Alliance.
The troops tried to remove checkpoints set up by the group on Monday in the centre of the city.
Port Sudan hosts the country’s only functioning airport. The city is also where some government officials and UN agencies have relocated amid the fighting in the capital, Khartoum, and elsewhere in the country.
Clashes between the Sudanese army and rival paramilitary Rapid Support Forces have left thousands of people dead since violence broke out in the capital, Khartoum, in April.