Several academics arrested at Khartoum University as protests continue

Sudan's security agencies have arrested several faculty members from Khartoum University, as protests calling for the removal of President Omar al-Bashir rocked the capital. 

Witnesses said security forces blocked professors and lecturers from coming out to protest outside the university, arresting at least eight. It was the first time the faculty of the country's oldest and most prestigious educational institution has joined the protests since they began last month.

The rest were forced to return into the faculty clubhouse, where security forces surrounded the building, trapping about 100 professors and lecturers inside for nearly three hours.

"We demand the president of the republic to step down," one placard read carried by the lecturers inside the club house, according to pictures posted on social media.

Riot police meanwhile fired tear gas at protesters in the capital ahead of a planned march on the presidential palace calling for Bashir to step down, witnesses have said.

"Police are not even allowing 10 people to gather," a witness told the AFP news agency.

Video footage posted on social media networks showed protesters fleeing down streets and alleyways in the capital, trying to escape the noxious gas.

Deadly anti-government rallies have rocked Sudanese cities since 19 December, when protests first broke out over a government decision to raise the price of bread.

Authorities say at least 19 people, including two security personnel, have been killed in clashes during the demonstrations so far, but rights group Amnesty International has put the death toll at 37.

The Sudanese Professionals' Association, a group of doctors, teachers and engineers, had called on Saturday for the march after organising similar rallies in recent weeks.

"We will march on the palace on Sunday calling for President Bashir to step down," the association had said in a statement.

Security forces were deployed to key squares across the capital on Saturday night ahead of the planned rally.

'Peace, justice, freedom'

Protests on Sunday also broke out in the city of Madani, southeast of the capital, witnesses said, with demonstrators chanting for "peace, justice, freedom".

An anti-government rally was held in the northern town of Atbara, where the current unrest first erupted last month.

Witnesses said the local market in Atbara was shut down as protesters took to the streets.

Sudanese authorities have launched a crackdown on opposition leaders, activists and journalists to prevent the spread of protests.

The country has been facing a mounting economic crisis over the past year, after a years-long foreign currency shortage worsened last year.

The cost of some commodities, including medicines, has more than doubled and inflation has hit 70 percent.

Late on Saturday, Bashir sacked Minister of Health Mohamed Abuzaid Mustafa, the official SUNA news agency reported.

He was replaced by Al-Khier Al-Nour, SUNA said, without giving details.

Rising drug prices and shortages have added to the anger of protesters already furious over the cost of other key products.

Sudanese pharmaceutical companies have been unable to import some medicines due to the foreign currency shortage.

Food and fuel shortages have been regularly reported across several cities, including Khartoum.