Five were killed in earlier attack on Mosque
While Washington's overnight attack on IS targets in Nigeria are, it said, a defence of Christians in the country, Muslims have suffered a security crisis as well.
Just two days ago, at least five worshippers were killed and 35 others injured when a suspected suicide bomber attacked a mosque in Maiduguri, the capital of Nigeria's Borno state, in the northeast.
Police said it happened during evening prayers, while no group has yet claimed responsibility for the attack.
Islamist insurgents Boko Haram and its ISWAP faction (see 7.39 for more on them) have waged a 15-year campaign of violence targeting civilians, mosques and markets in the northeast.
Witnesses at al Adum mosque described scenes of panic as victims were rushed to hospital.
Last August, gunmen attacked a mosque and nearby homes in the northwestern state of Katsina, killing at least 50, according to local officials and residents.
For context: Nigeria is a country of more than 200 million people, which is divided between the largely Muslim north and mostly Christian south.
An Islamist insurgency has dragged on for over 15 years and is largely confined to the northeast of the country, which is majority Muslim.
While Christians have been killed, most of the victims have been Muslims, analysts say.