ANTI-POLICE protesters in Nigeria stayed on the streets of Lagos, breaking a government curfew after a night of chaotic violence and reports of demonstrators being shot dead.

Shots were fired as youngsters set up barricades by the Lekki toll plaza in Lagos on Tuesday night, causing injuries and an unknown number of deaths.

There were reports of gunfire across the city of 14 million, including on the highway to the airport, at a major bus station and outside the offices of a tv station.

Demonstrations and gunfire were also reported in several other Nigerian cities, including the capital, Abuja.

Video from Tuesday night at the Lekki toll plaza shows protesters singing the national anthem in the darkness. Shots can be heard followed by sounds of people running away.

It is not clear who was firing the shots but Nigeria's security forces have been blamed for at least 10 deaths during the protests by Amnesty International.

There have also been widespread reports of youthful protesters being attacked by armed gangs, who demonstrators say were sent by the police to break up protests.

Lagos' governor, Babajide Sanwo-Olu, has ordered an investigation into the actions of the military at the plaza, an indication that the army may be responsible. He added that a governor cannot control how the military operate.

The curfew was announced after a police station was burned down in the city and two people were shot dead by police.

The protests began two weeks ago when a video showed a man being beaten, apparently by police officers of the Special Anti-Robbery Squad, known as SARS.