The demonstrations, a rare occurrence under a junta that has cracked down on criticism, were sparked by the arrest of an influential Sunni preacher on Tuesday.

Mohamad Ishaq Kindo had criticised a draft law regulating the exercise of religious freedoms in the west African country, where 60 percent of the population is Muslim.

After his arrest, people gathered at the mosque in the heart of the capital, Ouagadougou, to call for his release and were dispersed by security forces.

"Several dozen of them were taken into custody, some after car chases with the police," a resident said.

A security source told AFP that nearly 100 supporters of the imam had been detained in recent days and transferred to a camp for "civic and citizenship training".

A decree by the governor of the region of Ouagadougou ordered the closure of the mosque.

Under junta chief Captain Ibrahim Traore, who seized power in 2022, detainees are sometimes forcibly conscripted to fight jihadists on the front line.

The military authorities say it is necessary due to the more than decade-long battle against the armed groups, who are active in a large part of the country.

Earlier this week, the junta suspended the largest student union for three months and arrested its leader for "advocating terrorism".

It came after the union criticised repression and the junta's "obvious inability" to restore security in the country.

Four years ago, Traore had promised to defeat the jihadist groups within three months but violence continues killing thousands every year.