The army was deployed to reinforce security, government spokesperson Abdou Karim Fofana said.
Nine people were killed in clashes between riot police and Sonko supporters on Thursday, after the presidential aspirant was sentenced to two years for "corrupting youth."
Sonko's PASTEF party in a statement after the sentencing called on citizens to "stop all activity and take to the streets."
Cheikh Anta Diop University, in the capital Dakar, became the epicenter of the violence, as protesters set buses alight and threw rocks at riot police, who responded by firing tear gas.
On Friday, security forces patrolled Dakar's streets, which were strewn with burned tires, rocks and broken glass and lined with damaged residences and businesses. Large groups of students were bused out of the university campus with their belongings.
Thursday's riot was the latest bout in months of violent protests in Senegal, long considered one of West Africa's strongest democracies, sparked by Sonko's court case, but also, concerns that President Macky Sall will try to bypass the two-term limit and run again in February elections. Sall has neither confirmed nor denied this.
A criminal court cleared Sonko of rape, but found him guilty of a separate offense described in the penal code as "immoral behavior towards individuals younger than 21."
The verdict casts doubt on Sonko's chances of running for president next year, prompting the opposition to say it was politically motivated.