An explosion that ignited a fire at a petrol station in the Nigerian commercial capital, Lagos, has killed at least eight people, and has destroyed at least 25 homes, 16 shops and a primary school, the State Emergency Management Agency (Sema) has said.

The explosion occurred in the early hours of Thursday in Baruwa, a largely residential area.

The cause of the blast is still unclear, but the emergency services say a gas emission had been identified and contained.

This is the latest in a series of deadly explosions in Nigeria.

A fortnight ago about 30 people, including students, were killed when a lorry carrying fuel exploded in Lokoja, the capital of Kogi state in central Nigeria.

A day later dozens were injured in a similar incident in Lagos.

While the reasons for the explosions remain unclear, observers say it may be because of poorly maintained facilities and a lack of efficient means of transporting fuel to petrol stations.