Thousands of demonstrators across Sudan have taken part in what appears to be the largest demonstration row against President Omar al -bashir since the protests began in December.
Demonstrators arrived in Khartoum for the first time at Army headquarters. The presidential area is nearby.
Security forces used tear gas and batons to try to restrain demonstrators.
The rallies mark the 34th anniversary of the coup that overthrew the regime of former President Jaafar Nimeiri.
Why are people protesting?
The protests were originally triggered by an increase in the cost of living, but now demand that the reigning president for nearly 30 years resign.
The Sudan's economy has long been tense sanctions imposed since the US more than 20 years ago, accusing Khartoum of sponsoring terrorist groups.
On December 1
The year before, inflation was high, while the Sudanese pound quickly lost value.
The announcement of the price increases sparked protests that led to a call for President Omar al-Bashir to resign. Sudan
The biggest protests in memory have hit Sudan
His reign has been plagued with allegations of human rights abuses. In 2009 and 2010, he was indicted by the International Criminal Court (ICC) for genocide, war crimes and crimes against humanity. An arrest warrant was issued.
Who are the demonstrators?
The Sudanese Professionals Association (SPA) – a collaboration of health professionals and lawyers – has organized the protests.
Doctors have become a leading force and are therefore targeted by the authorities.
It is estimated that up to two-thirds of the protesters are women who say they are demonstrating against the sexist and patriarchal society of Sudan.
How did the president respond?
In February, it looked like he was giving in to protests and resigning, but instead, Mr. Bashir declared the national emergency.
Safety was heavy on the streets, with tear gas being used indiscriminately and reports of violence being commonplace.
The Sudanese authorities have been accused of detaining prominent activists and targeting doctors
According to the authorities, 31 people have died in protest but Human Rights Watch says the number is rather 51.
The Working Group of Doctors for Human Rights says that there are indications of killing, persecution and torture among peaceful demonstrators and the doctors who care about them.