It was the latest move in a long running tussle between President Macky Sall's ruling party and Sonko's Pastef, whose supporters say that Sall has used trumped up charges to sideline his popular opponent ahead of an election in February.
Pastef officials were not immediately available for comment.
Demonstrators took to the streets of Dakar once again on Monday as Sonko was remanded in custody by a judge on charges that include plotting an insurrection.
Sonko, who denies wrongdoing, was detained last week following a scuffle with security forces stationed outside his home in Dakar. It is not clear if Sonko will remain in jail or when a trial will begin.
"He will spend his first night in prison," his lawyer, Bamba Cisse, told Reuters.
Violent riots erupted across Senegal in June and at least 16 people were killed after Sonko was handed a separate two-year prison sentence for immoral behaviour towards individuals younger than 21. At the time, he called for protesters to take to the streets.
Protesters blocked the highway into Dakar on Monday with burnt tyres and trucks, snarling traffic even before the judge's ruling and the interior minister's statement.
Reuters reporters saw small sporadic groups of protesters clash with police, who fired tear gas. A train service linking Dakar with nearby Diamniadio was suspended.
The government restricted internet access due to the spread of "hateful and subversive messages" on social media.
(Reporting by Ngouda Dione and Joel Kouam; Writing by Anait Miridzhanian; Editing by Edward McAllister and Alison Williams)
By Ngouda Dione and Joel Kouam
