The Rapid Support Forces (RSF) of Sudan said it has seized control of Khartoum Airport and the Merowe military base in the north of the country, according to a statement issued on Saturday. 

Earlier in the day, fierce gunfire and sporadic artillery fire had been heard in Khartoum and other areas amid mounting tensions between the Sudanese army and the RSF. 

"The Rapid Support Forces defended themselves in response to the hostile forces inflicting heavy losses" on the regular army, the RSF statement said.  It said its fighters "were able to take control of Merowe airport and base" north of Khartoum, "expelled attackers on bases in Soba" and "took control of Khartoum airport." 

But the Sudanese army denied such claims and insisted later that it still controls all military bases and airports.

It said the RSF had tried to attack its troops in different positions and the Sudanese air force is conducting operations to confront the RSF.

Sudan has been suffering a political crisis since the Sudanese army commander Abdel Fattah Al-Burhan declared a state of emergency on October 25, 2021, and dissolved the sovereign council as well as the government.

On December 5, 2022, Sudan's military and civilian leaders signed a political framework agreement to end the political impasse and institute a two-year transitional civilian authority, but the two sides have so far failed to transform the agreement into a final deal.

They have agreed on most of the issues, with the exception of those relating to the reforms of the security and military forces, under which the RSF and other armed factions will be integrated into the Sudanese army.

(With input from Xinhua)