The fighting that erupted on Saturday in Khartoum, the capital of Sudan, was the culmination of months of rising tensions between two military leaders who only 18 months ago came together to seize power in a military coup.
The gunfire, explosions and chaotic scenes across the capital dashed the once heady hopes stirred by the 2019 revolution, when tens of thousands of Sudanese massed in the streets to force the ouster of President Omar Hassan al-Bashir, their autocratic ruler of nearly 30 years.
Those euphoric scenes led to Mr. al-Bashir being thrown into prison, and spurred hopes that Sudan could end decades of ruinous international isolation and turn to democracy.
But that optimism received a crushing setback in October 2021 when the military seized power in a coup.
The takeover was led by the army chief, Gen. Abdel Fattah al-Burhan, and Lt. Gen. Mohamed Hamdan, who commands the powerful Rapid Support Forces paramilitaries. But the two generals struggled to impose authority on Sudan’s fractious political scene.
The country’s economy tumbled deeper into trouble, and anti-military protests erupted practically every week in Khartoum, led by angry young Sudanese impatient for a transition to democracy.
And then the two generals themselves had a falling out.
What started over a year ago as private sniping between General Hamdan and General al-Burhan degenerated in recent months into barely veiled public attacks, delivered either by the two generals in speeches or in statements by close aides.
In December, under growing international pressure, the two generals agreed to hand power back to a civilian-led government, in a process that was due to culminate this month.
But the two generals squabbled over key issues, notably over how quickly their two rival forces should be integrated into a single army. Hard-liners inside the military wanted the Rapid Support Forces, estimated by foreign diplomats to number up to about 70,000 fighters, to disband within two years.
General Hamdan, who started out as a commander in the notorious Janjaweed militias responsible for atrocities in the western Darfur region in the 2000s, told negotiators that the process could take at least 10 years.
Both General Hamdan and General al-Burhan quietly reinforced their military forces at camps across Khartoum and in provincial capitals. Residents of Khartoum grew wary when they saw vehicles carrying troops and armored vehicles entering the city at night.
In an interview with The New York Times last month, Abdul Rahim Dagalo, the deputy commander of the Rapid Support Forces, accused General al-Burhan of being willing to allow the country to “burn.”
Tensions spiked last Wednesday when the Rapid Support Forces seized control of an army base in Meroe, 125 miles north of Khartoum. The army issued a statement in response accusing the R.S.F. of “disturbing the peace and spreading fear.”
That escalation prompted intensive diplomatic efforts to dial back the tensions, led by officials from the United Nations, the United States, Britain, the United Arab Emirates and Saudi Arabia.
But those efforts crumbled on Saturday morning when explosions and gunfire rang out across the capital.