Residents of Ogun state in Nigeria face arrest if found not wearing face masks in public, according to police spokesman Abimbola Oyeyemi.
The state is considered as a coronavirus hot-spot and was under a 35-day lockdown that ended last week.
Governor Dapo Abiodun had ordered mandatory mask-wearing as a precaution to stop the spread of coronavirus. The order took effect on 1 May and local leaders say people are not complying.
Enforcement will begin this weekend, the police said. Those arrested will be quarantined for 14 days while doing community work.
Ogun state has so far recorded 100 coronavirus cases and is at a high risk because of its proximity to commercial capital, Lagos.
