Protesters clashed with residents in Lagos on Friday during a demonstration against the country's worst cost-of-living crisis in a generation.
Carrying placards, bells and Nigeria's green-and-white flag, the protesters were met with a heavy security presence on the streets of Lagos.
The protests were mainly over food shortages and accusations of misgovernment and corruption in Africa's most populous country.
Nigeria's public officials are among the best paid in Africa, a stark contrast in a country that has some of the world's poorest and hungriest people despite being one of the continent's top oil producers.
"The purchasing power of my salary has been completely eroded," a protester told The Associated Press.
The mostly young protesters chanted songs as they listed their demands, including the reinstatement of gas and electricity subsidies that were cancelled as part of an economic reform effort.
Violence and looting were concentrated in Nigeria's northern states, which are among the hardest hit by hunger and insecurity.
Amnesty International's Nigeria office said at least nine people were killed by security forces in Nigeria during mass protests against the economic crisis gripping the country.
Authorities said a police officer was also killed and others injured, while four protesters were killed by a bomb.
Hundreds were arrested in the protests that triggered curfews in several states.
