Clashes between Sudan's main paramilitary group and the armed forces on Saturday killed at least 25 people, a doctors' group said, in an apparent struggle for control amid the country's halting moves toward elections after a military coup.
The Sudanese Doctors' Union said 183 people were wounded in fighting between the military and the Rapid Support Forces (RSF). It was unclear whether the victims were civilians.
The group said it recorded deaths at Khartoum's airport and the nearby city of Omdurman as well as in the cities of Nyala, El Obeid and El Fasher, which are west of the capital Khartoum.
The paramilitary RSF claimed to have seized the presidential palace, army chief's residence, state television station and airports in Khartoum, the northern city of Merowe, El Fasher and West Darfur state. The army rejected those assertions.
The Sudanese air force late on Saturday told people to stay indoors while it conducted what it called an aerial survey of RSF activity, and a holiday was declared in Khartoum state for Sunday, closing schools, banks and government offices.
Gunfire and explosions could be heard across the capital, where TV footage showed smoke rising from several districts and social media videos captured military jets flying low over the city. Eyewitnesses reported shooting in adjoining cities.
A Reuters journalist saw cannon and armoured vehicles deployed on the capital's streets and heard heavy weapons fire near the headquarters of both the army and RSF.
Army chief General Abdel Fattah Al-Burhan told Al Jazeera TV the RSF should back down: "We think if they are wise they will turn back their troops that came into Khartoum. But if it continues we will have to deploy troops into Khartoum from other areas."
The armed forces said on Facebook it would not negotiate with the RSF unless the paramilitary force dissolved. The army told soldiers seconded to the RSF to report to nearby army units, which could deplete RSF ranks if they obey.
The RSF leader, General Mohamed Hamdan Dagalo, better known as Hemedti, called Burhan a "criminal" and a "liar". The military and RSF, which analysts say is 100,000 strong, have been competing for power as political factions negotiate forming a transitional government.
"We know where you are hiding and we will get to you and hand you over to justice, or you die just like any other dog," he said in an interview with the station.
A prolonged confrontation between the RSF and army could plunge Sudan into widespread conflict as it struggles with economic breakdown and tribal violence, and could also derail efforts to move towards elections.
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