The US and the UK have closed their consulates in Nigeria’s biggest city, Lagos, citing “security fears”.

A spokesman at the US embassy in the capital, Abuja, said: “The embassy is reacting to a security incident and we thought it prudent to close.”

The Foreign Office in London said the UK had shut its mission in Lagos as a precaution following the closure of the US consulate, which is just 100m away.

The threat was of “mutual concern” to the US and Nigeria, diplomats say.

No further details have been released.

Nigerian police are investigating the incident and the BBC’s Anna Borzello in Lagos says there is a high security presence in the area.

Police are stopping passers-by and checking their bags, she said.

Other consulates on the same road on Victoria Island, Lagos, had also closed, a Foreign Office spokesman said.