Three explosions have struck the northeastern Nigerian city of Maiduguri shortly after Muslim Friday prayers, without causing any casualties, according to the military.

Maiduguri lies at the centre of a violent anti-government campaign by the Islamist group Boko Haram, which has been blamed for waves of bombings and shootings, including a Christmas Day bombing of a Catholic church that killed at least 37 people.

All of the Maiduguri bombs on Friday struck near market areas in different parts of the city, Mohammed Hassan, the military spokesman for Maiduguri, said by telephone, denying reports that one of them struck near a mosque.

In a separate incident, armed men shot dead three members of a Muslim religious leader's family dead, the military said.

The assailants stormed the family of the junior religious leader behind Maiduguri's railway quarters and shot dead his family.

"The Boko Haram sect members came this morning looking for Modu but as he had already gone out they opened fire on members of his family killing three of them," Baba Lawan, a witness, said.

Hassan, the military spokesman, said authorities believe the incident could either be a robbery attempt or another attack by the Boko Haram.

Separately on Friday, a hospital official said one more person died of injuries after a Christmas Day blast that struck St Theresa Catholic Church near Nigeria's capital, Abuja, bringing the death toll from the Christmas attacks to 42.

The official, who asked not to be named because he is not permitted to speak to the press, said the victim died late on Thursday.

A spokesman for the National Emergency Management Agency reported 37 deaths as of Thursday evening in the blast near Abuja.

Four more people were killed in other Christmas violence blamed on the Boko Haram, which wants to impose Islamic law in Africa's most populous nation.

The Boko Haram claimed responsibility for the co-ordinated attacks.

Source: Agencies