Sudanese security forces moved against a protest sit-in camp in the capital Monday, witnesses and protest organizers said. Machine gun fire and explosions were heard and smoke rose from the area.

Protest organizers said at least two people were killed.

The military’s move came after a weeks-long standoff with protesters seeking a speedy transition to civilian rule following the April ouster of long-time strongman Omar al-Bashir.

Dura Gambo, an activist, said large numbers of troops besieged the sit-in area outside the military’s headquarters in Khartoum on Monday and arrested protesters trying to leave.

“They have used the heavy rain yesterday and moved in the early morning to disperse people,” she said.

A statement by protest leaders said the military is trying to disperse the sit-in, and urged supporters to come to the area. The Sudan Doctors’ Association said at least two people were killed early Monday.

An Associated Press journalist saw buses and soldiers on foot blocking roads leading to the protest site. Civilians were not allowed to walk in the streets, including women and children.

Videos circulating online appeared to show protesters standing at low brick barricades in the street, then being driven back by walls of blue-clad security forces carrying sticks.

Other videos showed protesters running through streets lined with sit-in tents, heads down, as the sound of gunfire filled the air.

Thousands of protesters have been camped for weeks outside the military’s headquarters, the epicentre of Sudan’s uprising that led to the military overthrow of al-Bashir.

Protesters had vowed to remain in the streets after Bashir’s ouster, saying an end to his 30-year rule did not go far enough.

Protest leaders and military officials have been negotiating over the makeup of a transitional government, as protesters call for “limited military representation” in a sovereign council that would lead the country as it transitions to civilian rule over three years.

Both sides are split over the makeup and leadership of the council, with the ruling generals refusing to relinquish power.