At least eight people have been killed and 15 wounded in a bomb blast in north-eastern Nigeria. The incident occurred in Maiduguri, capital of restive Borno state, where a car laden with explosives hit a taxi part of a convoy to Gamboru, a town on the border with Cameroon, news agency AP said.

"We evacuated eight dead bodies and about 20 other injured persons," a rescue worker was quoted as saying. Borno is the epicentre of a seven-year-long insurgency carried out by Boko Haram terrorists.

The Nigerian army is leading a regional offensive – consisting of 8,700 troops from Nigeria, Niger, Chad, Cameroon and Benin – against Boko Haram.

The offensive has scored some successes, such as the recapture of key territories and the recovery of arms and vehicles used by the terrorists during their attacks.

Although Nigerian President Muhammadu Buhari declared a technical victory over the fight against the insurgents in December 2105, Boko Haram still carries out attacks, with security experts warning that underlying issues such as disenfranchisement, poverty and strong links with the Islamic State (Isis) will continue to pose major threats to stability in the region.

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Who are Nigeria's Boko Haram?

Boko Haram, which has renamed itself Iswap, fights against Western influence in Nigeria and aims to impose its version of Sharia law throughout occupied territories.

The group launches attacks in Nigeria and neighbouring countries in a bid to take control of more territory. Three Nigerian states – Adamawa, Borno and Yobe − have been under a state of emergency since May 2013.

Boko Haram has killed more than 20,000 people since 2009 and was deemed the world's deadliest terror group, surpassing Islamic State in November 2015. Nigeria has also become the world's third-most terrorised country as a result of the group's violent insurgency.

Boko Haram
Soldiers are seen on a truck along a road in Maiduguri in Borno State, Nigeria May 14, 2015 REUTERS/Stringer