Politician and publisher of Sahara Reporters, Omoyele Sowore, was arrested by officers of the Nigeria Police Force (NPF) in Abuja on Thursday morning.
Sowore was picked up shortly after exiting the Federal High Court in Abuja, where he had gone to show solidarity and meet with Nnamdi Kanu, the detained leader of the proscribed Indigenous People of Biafra (IPOB).
The details surrounding his arrest remain unclear, but witnesses said the police moved in swiftly as Sowore stepped out of the court premises.
Sowore, known for his outspoken activism and previous clashes with security agencies, has been a prominent critic of government policies and a consistent advocate for human rights and democracy in Nigeria.
As of press time, the police had yet to issue an official statement regarding the reason for his arrest.