Residents in Khartoum say they heard a large explosion near Sudan's army headquarters on Thursday, as fighting between rival groups continues despite modest holiday hopes.

Despite separate unilateral truces called for by the fighting generals for the holiday, huge columns of smoke emerged from the region of the military complex in the capital's heart on the second day of the Muslim feast of Eid Al-Adha.

Since mid-April, deadly combat between forces loyal to army chief Abdel Fattah Al-Burhan and the paramilitary Rapid Support Forces (RSF) has confined millions of Khartoum citizens, forcing them to ration electricity and water in the stifling heat.

Residents seven kilometers distant "felt the tremor in their walls," one of them told AFP. The source of the explosion could not be determined immediately, and there was no information on injuries.

In northwest Khartoum, army fighter jets launched “air strikes on RSF troops," witnesses said.

According to the Armed Conflict Location and Event Data Project, the horrific struggle between Al-Burhan and his former deputy, RSF leader Mohammad Hamdan Dagalo, has killed at least 2,800 people.

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The figure is cautious, with many of the injured unable to reach medical facilities and bodies left to fester on the streets of Khartoum and the western area of Darfur, where most of the bloodshed has taken place.

The violence has forced 645,000 people to escape across borders, with an additional 2.2 million displaced within the country, according to the UN

Experts believe both sides refuse to negotiate before claiming military advantage, and the combat, which began on April 15, shows no signs of abating.

Al-Burhan last week urged Sudanese "youth and all those able to defend" to join the military in fighting the "existential threat" presented by the RSF.

Civilians have generally rejected the appeal, heightening concerns that what began as a power struggle between generals is escalating into civil war.

The UN has warned that RSF and allied militia attacks in Darfur could amount to "crimes against humanity."

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Two days earlier, Sudan's Rapid Support Forces (RSF) announced 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.

Likewise, the Sudanese army declared, in a televised address, a "unilateral" ceasefire on the first day of Eid.

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