Senegal's leading opposition party, whose leader Ousmane Sonko is accused of rape, said on Monday police had arrested almost 80 of his supporters, calling them "political hostages".
Sonko was accused of rape in early February by a beauty salon employee, which he denies and claims is a political plot created by President Macky Sall. His supporters subsequently clashed with police during protests outside Sonko's residence in Dakar on February 8.
Sonko, the 46-year-old head of the opposition Pastef party, came third in the 2019 presidential election, which saw President Sall win a second term in office, and is considered a future presidential contender in the West African state.
Ousseynou Ly, a Pastef spokesman, told AFP that 77 "political hostages" are in detention.
Senegal's police did not respond to a request for comment by the news agency.
On Monday, a coalition of 20 teachers' unions also called for a 24-hour strike in protest at the alleged arrest of two teachers who support Sonko.
Last week, Senegal's parliament stripped Sonko of his legal immunity, opening the way towards a police investigation of the complaint.
The rape allegation against the opposition leader comes amid uncertainty over whether Sall, 59, will seek a third term.
Presidents in the former French colony of about 16 million people are limited to two consecutive terms, but Sall launched a constitutional review in 2016, raising suspicions he intends to run again.