Sudanese authorities closed two of the Nile bridges in the capital Khartoum on Tuesday and brought in shipping containers to seal off other bridges in anticipation of mass rallies planned on Wednesday demanding an end to military rule
Security has also been shored up around some of the meeting points announced by organisers of pro-democracy groups, witnesses said.
These include the Republican Palace in central Khartoum, the nearby army headquarters, the parliament in the sister city of Omdurman, and the barracks of the armoured corps south-west of the city.
The rallies planned on Wednesday will be the latest in near-daily protests against military rule since army chief Gen Abdel Fattah Al Burhan seized power last October, a move that derailed the country's democratic transition and led to an economic crisis.
Since then, security forces have dealt violently with the rallies, killing more than 90 protesters and injuring about 3,000.
“We will take to the streets on April 6 for the sake of the change we dream of,” said the Sudanese Professionals Association, a key pro-democracy group. “We will be out on the glorious day of April 6 with our heads held high and the bravery of our people known to all.”
The resistance committees, a grass roots movement that has led protests since the October takeover, also called on their supporters to come out on Wednesday, ensuring a sizeable turnout.
The witnesses said the key bridges of Maknimir and Kobar have been sealed off since Monday night.
Security forces have also ferried shipping containers to the city’s other Nile bridges and placed them close to their entrances.
The rallies mark an uprising in 1985 that toppled the 16-year rule of military dictator Jaafar Al Nimeiri and also the start of a sit-in outside the army headquarters in 2019 calling for the removal of long-time dictator Omar Al Bashir.
While army generals removed Al Bashir on April 11 that year, the protests continued, demanding that the military hand over power to civilians.
On June 3, security forces violently broke up the rally, killing more than 100 protesters and throwing some of the bodies in the Nile.
Two months later, the pro-democracy movement and the military reached a transitional, power-sharing deal, which Gen Al Burhan discarded when he seized power just weeks before he was to hand over his de facto head of state position to a civilian.
An investigation into the break-up of the sit-in has yet to publish its findings more than two years after it began its work.
Also, little is known about the fate of investigations ordered by Gen Al Burhan to look into the killing of protesters since his takeover and alleged sexual assault by security forces of female protesters.
In Khartoum on Tuesday, security had been stepped up across the city amid widespread speculation that internet and telephone services would be severed by authorities on Wednesday to deny organisers the chance to coordinate.
Gen Al Burhan last week threatened to expel the UN special representative in Sudan, accusing him of overstepping his mandate.
He has said he will only hand over power to an elected government, suggested that the pro-democracy movement was a tool in the hands of Sudan’s foreign “enemies”, and equated with treason any opposition to military rule.
His second-in-command, paramilitary commander Gen Mohamed Hamdan Dagalo, has accused antimilitary activists of being agents on the payroll of foreign embassies.
Meanwhile, most Sudanese are unable to make ends meet in the face of rising prices of essential food items and fuel.
The value of the pound has plummeted against the US dollar and power outages have become more frequent at a time of year when the temperature routinely hovers around 40°C.