Nigerian police have fired tear gas at a protest against police brutality in the capital Abuja.
A video of a man allegedly being killed by police sparked the latest protests.
Several other protests have taken place across Nigeria, including Lagos. Star Wars actor John Boyega is among the celebrities supporting the protesters.
The movement initially targeted the highly-criticised federal Special Anti-Robbery Squad (Sars), widely accused of unlawful arrests, torture and murder.
The hashtag #EndSARS was trending worldwide on Twitter on Friday with celebrities including the Nigerian superstars Wizkid and Davido tweeting their support for protesters.
More and more Nigerians started using the hashtag last Saturday following the alleged killing of a young man by officers from the Sars unit.
Many people were also using the hashtag to share stories of brutality attributed to the police unit.
On Sunday Nigeria’s inspector general of police Mohammed Adamu banned the Sars unit from carrying out stop and search duties and setting up roadblocks.
He also said members of Sars must always wear uniforms and promised the unit would be investigated.
But protesters want the unit disbanded completely.
Gunshots heard
On Friday protesters marched to the police headquarters in Abuja.
An eyewitness, protester Brian Dennis, told the BBC that police used tear gas and some protesters were beaten up.
Videos shared on Twitter appear to show protesters running away from tear gas.
Another protester Anita Izato said she heard gunshots and protesters ran to safety.
It is the second day of protests against the police in Nigeria and in the biggest city, Lagos, protesters slept overnight outside government house.