Protesters in Khartoum have taken to the streets to demand that President Omal Hassan al-Bashir quit, witnesses said, after days of unrest in which dozens of people have been killed.
Daily demonstrations this week followed the government cutting fuel and cooking gas subsidies on Monday when pump prices doubled overnight.
Four protesters were shot dead by unidentified gunmen on Friday, police said, bringing the official death toll to 33.
In Khartoum's Burri district, home to a top government official, more than 1 000 people gathered for the funeral of one of the victims, Salah Sanhuri, a doctor from a prominent merchant family with strong ties to the government.
More than 2 000 people joined the funeral procession, shouting, "Freedom, freedom," and "The people want to overthrow the regime", blocking a main road, witnesses said.
On Friday, more than 5 000 people demonstrated in Khartoum, the biggest turnout in central Sudan for many years. Its borderlands have grappled with insurgencies for decades but the relatively wealthy heartland has seen little turmoil in the recent past.
Police said in a statement unknown gunmen had opened fire on a group of protesters on Friday, killing four people.
Khartoum has been brimming for days with armed civilians and security personnel carrying rifles, patrolling streets in broad daylight and manning rooftops. Opposition activists have accused Bashir's National Congress Party of vandalism and of arming militias to turn the public against the protesters.
Bashir, who seized power in a 1989 coup, has not faced the sort of Arab Spring uprising that unseated autocratic rulers from Tunisia to Yemen since 2011, but anger has risen over corruption and rising inflation in the vast African country.
He has stayed in power despite rebellions, US trade sanctions, an economic crisis, an attempted coup last year and an indictment from the International Criminal Court for war crimes. He still enjoys support from the army, his ruling party and many business men.
The subsidy cuts have been driven by a severe financial crunch since the secession of oil-producing South Sudan in 2011, which deprived Khartoum of three-quarters of the crude output it relied on for state revenues and food imports.
Amnesty International and the New York-based African Center for Justice and Peace Studies said at least 50 people had been killed by gunshots to the chest or head by Thursday night, citing witnesses, relatives, doctors and journalists.