The attacks on Maiduguri began with rocket-propelled grenades which killed at least 13 people and injured a number of others on Saturday. Several homes were destroyed in a suburb about 20 kilometers (12 miles) west of the city center. An intelligence officer said Boko Haram fired the grenades.

Later on, a man was seen pushing a wheelbarrow near a mosque in the city. He was pretending to be an itinerant trader from the nearby marketplace moving towards the mosque to join in afternoon prayers, according to witnesses and police.

The man then exploded a device, killing himself and 26 others near the Alhaji Haruna mosque next to Maiduguri's Monday Market area. A further 28 people were injured.

There was no immediate claim of responsibility but the Monday Market has been hit by several suicide bombings blamed on Boko Haram.

Maiduguri is the capital and the largest city of Borno State in north-eastern Nigeria where the Boko Haram terror group began and has launched multiple attacks over the last six years. An estimated 13,000 people have been killed over that period, and the city's population of 2 million has been increased by the hundreds of thousands of refugees who have taken refuge there after fleeing their homes.

New government strategy

An offensive launched in February by Nigeria - with backing from neighboring Cameroon, Chad and Niger - has driven Boko Haram fighters out of a number of towns they controlled in the north east to the Sambisa Forest. But they have moved back into the region.

At his inauguration on Friday, President Muhammadu Buhari said he would move the headquarters for the offensive against Boko Haram from Abuja, Nigeria’s capital, to Maiduguri. The city would be reinforced with a new command and control center to improve the counter-insurgency effort.

Victims of the conflict, especially in the northeast, voted overwhelmingly for Buhari in the March elections, in part because the former-army general and dictator was seen as a strong commander-in-chief.

jm/jr (AFP, AP)