Thousands of protesters held a sit-in outside Sudanese President Omar al-Bashir's residence in central Khartoum on Sunday, having camped there overnight following the biggest demonstration in months of protests against his 30-year rule, witnesses said.
At least one person died on Saturday during "rioting" in Omdurman, Khartoum's twin city, state news agency SUNA said, without giving details on the cause of death.
Sudan has seen months of mostly small but sustained protests against Bashir's rule in which dozens of demonstrators have been killed. Security forces have used tear gas, stun grenades and live ammunition to disperse protests, witnesses have said.
Bashir has refused to step down, saying that his opponents need to seek power through the ballot box.
Since the sit-in began on Saturday, security forces tried several times to clear the protesters from the compound's vicinity using tear gas, including on Sunday morning, but thousands remained.
Apparently emboldened by the success of similar but much larger protests in Algeria which forced ailing President Abdelaziz Bouteflika to step down last week, Sudanese activists called for Saturday's protests to mark the anniversary of the 1985 military coup that overthrew autocratic president Jaafar Nimeiri following mass protests against his rule.
The protesters urged the military to side with them once more in their bid to push Bashir out of power.
Apart from Bashir's residence, the compound, the most heavily-guarded in Sudan, also houses the Defence Ministry and the headquarters of the powerful National Intelligence and Security Service.
Thousands of protesters also gathered in the Burri neighbourhood of Khartoum on Sunday, where they blocked several main roads, witnesses said.
The person killed on Saturday was a laboratory doctor who died of his injuries, according to a statement from an opposition doctors' committee. Medical staff have played a prominent role in the protests.
SUNA said other civilians and police officers were also wounded on Saturday in Omdurman, which saw protests late into the evening that subsided by Sunday morning.
The sit-in outside the compound appeared to mirror 2011 "Arab Spring" protests, when demonstrators in Cairo and other Arab capitals camped out in public squares for days demanding a change in rule.
Police and security forces on Saturday blocked all bridges leading to the capital's centre from Khartoum North and Omdurman, across the River Nile to the north and west respectively, in what appeared to be a bid to prevent the sit-in from swelling.
They remained closed on Sunday, causing major traffic jams. Hundreds of people were crossing into Khartoum from Omdurman via Victory Bridge by foot on Sunday morning, a Reuters witness said, as cars stood at a standstill for hours.