At least 24 people have been killed here in clashes sparked by cuts in fuel subsidies, BBC reported Wednesday citing sources.
The director of Omdurman hospital in the Sudanese capital said his staff had seen 21 bodies. Three others died at another hospital.
Earlier police fired tear gas at protesters. The unrest began Monday when the government lifted fuel subsidies to raise revenue.
Sudan's economy has been in trouble since South Sudan ceded in 2011.
Osama Mortada of Omdurman hospital said that 21 people sent to his hospital had died, and that about 80 were injured.
"All have gunshot wounds, some in the chest," he said.
Sources at the Khartoum Bahari hospital said Wednesday that the facility had received three bodies "shot by live bullets".
Groups of anti-government demonstrators set fire to a university building and several petrol stations in the national capital Khartoum.
They blocked a main road to the airport and burnt a number of cars, according to witnesses.
Sudan had experienced an oil-fuelled economic boom until South Sudan became independent, taking 75 percent of its oil reserves.
The government reduced some fuel subsidies in July 2012, prompting several weeks of protests and a security crackdown.