Thousands of protesters held a sit-in outside Sudanese President Omar al-Bashir's residence in central Khartoum on Sunday, chanting anti-government slogans at several main streets.

The North African country has seen sustained protests against Bashir and his National Congress Party since December 19. Security forces have fired tear gas, stun grenades and live bullets to disperse protesters and dozens have been killed during demonstrations.

Bashir has refused to step down, saying that his opponents need to seek power through the ballot box.

On Sunday evening, dozens of demonstrations took place in the capital city Khartoum, where protesters   set fire to tires and blocked a main road. Demonstrators also blocked a bridge that connects Khartoum and Khartoum North. 

Earlier, Sudan suffered a total power blackout, the ministry of water resources, irrigation and electricity said without explaining the cause of the outage. Electricity was later restored in some areas.

Since the sit-in began outside of the presidential residence on Saturday, security forces had fired tear gas several times in an attempt to clear the crowds, but thousands remained on Sunday.

The compound is the most heavily guarded area in Sudan. It is also home to the defense ministry and the headquarters of the powerful National Intelligence and Security Service.

On Saturday, at least one person died during protests in Omdurman, across the Nile from Khartoum, according to Sudanese state news agency SUNA.

Police and security forces on Saturday blocked all bridges leading to the capital's center 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.