Senegalese security forces on Friday used tear gas to disperse people attempting to gather in the capital after being urged to mobilise against a last-minute delay of presidential elections.
Anti-riot police kept back groups of people trying to get to the large Place de la Nation in central Dakar, where a rally had been planned.
Some demonstrators responded by throwing stones and all access points to the square were closed off, AFP journalists saw.
"The situation is deplorable. We came to pray and we got gassed. It's intolerable," Thierno Alassane Sall, one of the 20 candidates who had been due to vie for the presidency, told AFP.
"The Senegalese must be outraged and not just on social media."
In a test of the balance of power between President Macky Sall and opponents, people were urged to show their opposition Friday to Sall's sudden decision to postpone the February 25 election by 10 months.
On Monday, parliament backed the move, sparking a fierce opposition backlash and international concern.
The unprecedented move has called into question the West African country's reputation for democratic stability in a region beset by military coups.
Teachers were urged to walk out by education unions within the civil society platform Aar Sunu Election (Let's Protect Our Election).
At Blaise Diagne high school in Dakar, hundreds of pupils left their lessons mid-morning after teachers heeded the call.
History and geography teacher Assane Sene said it was just the start of the battle.
"If the government is stubborn, we will have to try different approaches," he said.
At the Masjidounnour mosque in Dakar, only a handful of worshippers followed a call to dress in white and the national colours.
"The message hasn't got through enough. But the situation in the country is deplorable, nobody's happy," 37-year-old Amadou Sy told AFP before Friday's main Muslim prayer.
In his sermon, Imam Ahmed Dame Ndiaye railed against the political situation.
"Even the president can make mistakes, and in that case it's up to us to tell him the truth", he said, adding that "nobody has the right to watch society being destroyed".
The Aar Sunu Election platform has also asked Christians to dress in white for church on Sunday and is planning a demonstration on Tuesday.
The vote by MPs to delay the presidential election paves the way for Sall -- whose second term expires in early April -- to remain in office until his successor is installed, probably in 2025.
A new date for the presidential election has been set for December 15.
The decision has unleashed widespread anger on social media and the opposition has condemned it as a "constitutional coup".
But Sall is showing no signs of backing down, said Sidy Diop, deputy editor of Le Soleil daily.
"He has never backed down, for him it's a question of self-respect", said Diop.
However, he added that the head of state is "in a very bad position".
If civil society and the opposition "manage to impose a balance of power unfavourable to the government and rally the international community, the president may then back down", he added.
International pressure may also have an impact, according to Alassane Beye, a lecturer-researcher at the University of Saint-Louis.
Beyond the online reaction, the outcry had until now only materialised into sporadic reaction on the streets.
Protests usually require authorisation and security forces quashed attempts to demonstrate and arrested dozens of people.
Rights advocates say the authorities have in recent years routinely banned opposition demonstrations.
Since 2021, dozens of people have been killed and hundreds arrested during various episodes of unrest in the country.
Sall said on Saturday he postponed the election because of a dispute between parliament and the Constitutional Council over would-be candidates who were not allowed to stand.
Parliament approved the delay to the ballot at a heated session, but only after security forces stormed the chamber and removed some opposition deputies.
The vote was approved with the support of members of Sall's parliamentary party and those of one would-be candidate banned from standing.
Sall told a cabinet meeting on Wednesday he wanted the authorities to take "pragmatic" steps to calm tensions and foster "reconciliation", his office said.
It did not detail what those measures would be.
After months of speculation that he was considering running for a third term, Sall said in July he would not stand again and has repeated that commitment several times.
