Police fired tear gas at groups of demonstrators who built makeshift barricades along one of Dakar's main highways. In one neighborhood, cars were gutted by fire and a ministerial building was set alight.
It is the latest round of months of unrest triggered by President Macky Sall's refusal to rule out running for a third term in office and by court cases involving a leading rival, Ousmane Sonko, who denies wrongdoing and says the charges are aimed at ruling him out of presidential elections next February.
Police escorted Sonko to his house on Sunday after a caravan of vehicles including he and some supporters had planned to enter Dakar.
"Sonko can't leave his house... No-one can go see him, but why? Where is this democracy?" said El Malick Ndiaye, a spokesman for Sonko's Pastef party.
The police and Sall's office did not respond to requests for comment on Monday.
Senegal is seen as one of West Africa's strongest democracies, and it has a two-term limit for presidents. But critics of Sall worry that he will use a change in the constitution in 2016 as an excuse to reset his mandate and run again, as other long-standing rulers in the region have done.
Sonko has strong support among young people, but his degrading comments last week about a woman who accused him of rape in a massage parlor in 2021 sparked backlash from Senegalese women's groups and dozens of well-known figures.
Last week, a prosecutor in Sonko's trial requested a 10-year prison sentence.