Senegalese police clashed with protesters in several neighbourhoods of the capital Dakar on Friday, including in front of a courthouse where an opposition leader made his first appearance since his arrest on a rape charge.
A lawyer for Ousmane Sonko said he was being charged with rape and making threats, allegations that have led to clashes since his arrest on Wednesday between his stone-throwing supporters and police in several towns.
Four people have died in the violence, Senegal's Interior Minister Antoine Felix Abdoulaye Diome, said in broadcast on national television on Friday, calling the protests as an "organised insurrection."
Sonko, a 46-year-old tax inspector with a strong following among young people, has denied wrongdoing and says accusations are part of a pattern by the authorities of making up criminal charges to block opponents from standing in elections.
On Friday in Dakar, protesters lobbed rocks and other objects at security forces, set up street barricades and burned tyres and debris, while police fired tear gas and stunt grenades to dislodge them.
Authorities have responded by curbing access to the internet and suspending broadcasting by two private TV channels that covered the protests. On Friday they also banned motorcycles and mopeds, popular among Sonko's young political base, from the streets of the capital.
Internet monitor NetBlocks said social media and messaging apps including Facebook, WhatsApp, and YouTube were restricted early on Friday. Bracing for violence, some schools and shops were shut.
Police in full protective gear guarded the courthouse as Sonko appeared before a judge. The hearing will resume on Monday.
United Nations representative in the region Mohamed Ibn Chambas in a statement on Friday called for restraint and calm, and urged the Senegalese government to "take the necessary measures to ease tensions."
One resident said a coronavirus pandemic-linked curfew and general dissatisfaction with President Macky Sall was also fuelling public anger.
"I don't think things will be calm. People are rising up," said 24-year-old fashion worker Souleymane Diallo.
The interior minister said the government plans ease coronavirus restrictions soon, as the West African nation has started inoculations against Covid-19 last week.
An employee of a beauty salon accused Sonko last month of raping her. Parliament stripped Sonko of his immunity as a lawmaker last week.
The opposition fears the case is an attempt by Sall to remove a potentially popular rival if he decides to seek a third term in 2024.
Other rivals have been targeted by criminal charges in the past, including former Dakar mayor Khalifa Sall and Karim Wade, the son of former President Abdoulaye Wade, eliminating them from the 2019 presidential race.
The government denies political motivations behind the case. Sall, 59, in power since 2012, has not commented on reports he might seek a third term despite a constitutional two-term limit.
Amnesty International expressed concern over the authorities' handling of the situation, citing a wave of arrests, the use of live weapons and the suspension of the broadcasters.