Marguerite Gnakade, sister-in-law to the west African nation's leader Faure Gnassingbe, called for his resignation two months ago in a period of rare anti-government protests.

"She was arrested for serious acts, including her recent public appearance inciting the military to rebellion," a police source told AFP.

Local media outlet Republic of Togo, citing security sources, reported that Gnakade was "being questioned by the competent authorities".

Gnakade, who was minister from 2020 to 2022, had published several opinion articles in recent months critical of the government of Gnassingbe, who has been in power since 2005.

"Keeping Faure Gnassingbe in power any longer will change nothing. He must responsibly resign to make way for a peaceful, inclusive, and national transition, aimed at rebuilding our country," she wrote last month.

On August 30, she supported a street protest called by bloggers and artists, before being stopped by security forces.

In late June, protesters staged several days of rallies during which at least seven people were killed, according to civil groups.

Protesters demonstrated against the arrests of government critics, rising electricity prices and a constitutional revision that allowed Gnassingbe, 59, to strengthen his grip on power.