Gunfire incidents and attempts to break into prisons have been reported in Nigeria, as rioting sparked by shelling of protesters in its largest city continues.

Rights monitoring group Amnesty International said security forces killed at least 12 people in Lagos on Tuesday (20/10).

The Nigerian army has denied killing demonstrators in the Lekki area, sparking more outrage.

The protests began about two weeks ago when demonstrators, mostly young people, demanded the dissolution of a notorious police unit.