Police in Nigeria's commercial capital, Lagos, have arrested 1,400 people in just a week for flouting measures to stop the spread of coronavirus after the lifting of a lockdown.

The measures include a curfew from 20:00 to 06:00 local time, mandatory wearing of face masks in public and a ban on inter-state travel.

In a statement, Commissioner of Police Hakeem Odumosu said that 820 people were arrested for violating the curfew, and about 130 people were arrested for not wearing face masks.

Lagos Governor Babajide Sanwo-Olu on Sunday warned that the lockdown could be reintroduced if residents continued to ignore social distancing rules.

There has been concern over the tactics used by security officers in the wake of the pandemic. The national human rights commission has said that security forces killed at least 18 people during the lockdown.

President Muhammadu Buhari previously said the government would not tolerate human rights abuses carried out by security agencies.

The west African country has confirmed 4,641 cases in total and 150 deaths.