For two weeks now, Mayowa Olayinka has joined thousands of demonstrators in the Nigerian commercial capital of Lagos to protest against police brutality.

"Things just can’t go on this way,” said the 18-year-old student, who noted that his cousin was killed by the police in 2015 when he refused to surrender a smartphone during a search. The policemen "boasted they would waste him and nothing would happen.”

Young Nigerians like Olayinka, many born after the end of military rule in 1999, have poured onto the streets of Lagos and other cities in some of the biggest demonstrations of the country’s democratic era. The protests have been fueled by social media, and come after the Black Lives Matter movement in the U.S.