Thousands of demonstrators took to the streets across Sudan on Monday to call for disbanding former President Omar al-Bashir's party.
Meanwhile, Sudan's transitional government and a main rebel faction signed a political declaration amid peace negotiations that began last week, taking a new step toward ending the country's yearslong civil wars, the Associated Press (AP) reported.
The whe two sides also renewed a nationwide ceasefire for three months.
The protests in Khartoum and other parts of the country coincided with the anniversary of an uprising in 1964. That push ended six years of military rule in Sudan following a wave of riots and strikes.
Sudan's current transitional government came to power after a similar campaign of mass unrest, which eventually led the military to overthrow al-Bashir.
The country is now ruled by a joint military-civilian administration, which must navigate a delicate path toward eventual democratic elections in just over three years.
There were no reports of any clashes with police or casualties during Monday's protests.
The marches renewed demands for independent investigation into the deadly break-up of a protest camp by security forces in June.
According to AP, the police blocked off main streets Monday leading to the presidential palace and the military's headquarters in Khartoum.
A statement by the police warned against "creating a state of chaos," which it said could lead to "unfavorable consequences."
Videos circulated online showed protesters marching in the capital and other cities such as Atbara, a northern transport hub where the uprising began in December.