Khartoum (AFP) - Sudanese police fired tear gas on Sunday at protesters ahead of a planned march on parliament in Omdurman, the twin city of Khartoum, witnesses said.
Demonstrators chanting "freedom, peace and justice" began gathering in some areas of Omdurman but were quickly confronted by riot police with tear gas, the witnesses said.
Deadly protests which erupted on December 19 after a government decision to raise the price of bread have turned into nationwide rallies against President Omar al-Bashir's three decade rule.
Officials say at least 26 people, including two security personnel, have died during a month of protests, while rights group Amnesty International last week put the death toll at more than 40.
The Sudanese Professionals Association, an umbrella group of trade unions that is leading the ongoing protest movement, called for fresh demonstrations on Sunday and several days over the coming week.
"We are calling for a march to parliament in Omdurman on Sunday," it said in a statement.
"The protesters will submit to parliament a memorandum calling on President Bashir to step down," added the association, which represents the unions of doctors, teachers and engineers.
The SPA said there will also be rallies in Khartoum on Sunday, to be followed by night-time demonstrations on Tuesday in the capital and in Omdurman.
"And on Thursday there will be rallies across all towns and cities of Sudan," the statement added.
On Sunday, protesters also staged a demonstration in the capital's eastern district of Bahari, witnesses said.
The government's tough response against demonstrators has sparked international criticism, while Bashir has blamed the violence on unidentified "conspirators".
Analysts say the protests have emerged as the biggest challenge yet to the authority of the veteran leader, who swept to power in 1989 in an Islamist-backed coup.
The protests come as Sudan suffers an economic crisis driven by an acute shortage of foreign currency and soaring inflation that has more than doubled the price of food and medicines.
A doctors' committee linked to anti-government protests apologised on Sunday for incorrectly reporting that a child had been killed in demonstrations in Khartoum that took place on January 17.
Sudanese police said that two people had died in demonstrations that rocked Khartoum on Thursday, but protest organisers had reported that three people were killed, including a child, in clashes with riot police.
"This mistake happened because we trusted a confident source, but we are now investigating the matter," a committee of doctors linked to the SPA said in a statement on Facebook, confirming that two people had died in the demonstrations on Thursday.
Riot police had on Thursday broken up a march on the presidential palace in Khartoum, while a rally took place later that day in the capital's Burri district, witnesses said.