Sudan's Rapid Support Forces (RSF) announced on Monday a unilateral ceasefire during the Eid Al-Adha Islamic holiday, effective on Tuesday and Wednesday.

RSF chief General Mohammad Hamdan Dagalo made the announcement in an audio recording broadcast on a major Saudi media outlet.

On the same day, the Sudanese army faced a multi-front challenge after losing a Khartoum police headquarters to the RSF in a battle that killed at least 14 civilians.

The RSF, which since mid-April has been fighting Sudan's regular army, announced late Sunday a "victory in the battle for the police HQ" of the Central Reserve paramilitary police.

"The headquarters is under our complete control... and we have seized a large number of vehicles, arms and munitions," the RSF claimed in a statement.

The army denied in a statement that the RSF had won a "military victory" and denounced "a flagrant attack against state institutions that protect civilians."

If the RSF maintain their hold on the strategic site at the southern edge of the capital, it "would have a major impact on the battle of Khartoum," a former army officer told AFP, requesting anonymity for safety reasons.

According to the former army officer, the Central Reserve headquarters gives the RSF "control of the southern entrance to the capital."

The sources explained that the presence of the RSF in that area poses "a serious threat" to the nearby headquarters of the armored corps, a key army unit in south Khartoum.

An army source, not authorized to speak to the press, said the RSF lost "more than 400 men" in the Central Reserve battle.

RSF have not provided any casualty figures but claimed their operation against the police facility led to the killing or capture of hundreds of army-linked personnel.

Troops were also battling hundreds of kilometers (miles) south in Kurmuk, near the border with Ethiopia, where residents said an armed group attacked army positions.

The armed group, a faction of the Sudan People's Liberation Movement-North (SPLM-N), had opened a new front against the army last week in South Kordofan state by attacking soldiers, the army said at the time.

The faction, led by Abdelaziz Al-Hilu, was one of two holdout groups that refused to sign a 2020 peace deal.

Nearly 2,800 people have been killed across Sudan since a power struggle between army chief Abdel Fattah Al-Burhan and his former deputy Dagalo broke out more than two months ago, according to the Armed Conflict Location and Event Data Project.

Residents said fighting continued on Monday in the area of the Central Reserve base, adding that RSF shells targeting an army checkpoint wounded civilians on a bus.

On Sunday, "14 civilians including two children were killed" in the same area, according to a network of activists who try to evacuate wounded to the few hospitals still operating.

The activists said 217 others were wounded, "including 72 in critical condition," by "stray bullets, air raids, or shelling" in residential neighborhoods of Khartoum's south.

Doctors without Borders (MSF) reported on Monday that in the past 48 hours, 150 war-wounded had been treated at Khartoum's Turkish Hospital.

"The majority of patients are civilians -- including children and the elderly," MSF highlighted on Twitter.

Two-thirds of Sudan's health facilities in the main battlegrounds remain out of service, the World Health Organization said, with some bombed and others occupied by fighters.

The few hospitals still operating are extremely low on medical supplies, struggling to obtain fuel to power generators, and understaffed.

Darfur, a vast western region on the border with Chad, has witnessed the deadliest violence since the war erupted on April 15.

In the South Darfur state capital, Nyala, at least a dozen civilians were killed on Sunday, according to a local doctor who spoke on condition of anonymity for security reasons.

Residents reported intense artillery fire overnight Sunday to Monday. "Rockets are falling on civilian homes," one of them told AFP.

Around two million people have been displaced within the country, and roughly 600,000 others have fled over Sudan's borders, the International Organization for Migration has said.

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