At least 11 people in Nigeria's north-eastern city of Maidugur after an attack by Boko Haram.
Panicked soldiers fired into the air, witnesses said, adding to the fear and confusion during the rush hour attack on Baga Road.
The blast was followed by a blinding sandstorm and then the first rains of the year, hampering rescue efforts.
Rescue workers near the site of an earlier explosion in Maiduguri.
Witness Issa Audu said he counted 11 bodies before he fled.
Maiduguri, the city where Boko Haram was created, has suffered daily attacks that have killed more than 50 people since the weekend.
They include suicide bombs, planted bombs and rocket-propelled grenades fired into homes as people slept.
The attacks started after newly-inaugurated president Muhammadu Buhari announced on Friday he is moving the command centre for the fight against Boko Haram to Maiduguri, at the heart of the war zone against Nigeria's home-grown Islamic extremists.
Earlier yesterday, the defence ministry announced that Major General Tukur Yusuf Buratai has taken charge of the multinational force fighting Boko Haram. That takes the lead role away from neighbouring Chad.
The Nigerian army "remains a virile fighting force ... capable of routing Boko Haram", Mr Buhari declared on a visit to Niger, which is contributing troops and hosting hundreds of thousands of Nigerian refugees from the violence.
The appointment came the day before he is scheduled to visit N'Djamena, the Chadian capital that is the headquarters of the multinational force.
Before his election, Mr Buhari, a retired major general who was briefly a military dictator in the 1980s, had said the presence of foreign troops on Nigerian soil was "a national disgrace".
He has promised to co-operate fully with Chad and Niger, which had complained that a lack of co-operation was hampering the war.
Battle-hardened Chadian troops took the lead in an offensive this year that drove Boko Haram from north-eastern towns where the extremist group had declared an Islamic caliphate.
But the Chadians several times have had to retake some Nigerian towns seized back from Boko Haram because Nigerian troops did not arrive to secure them.
The insurgents continue hit-and-run attacks and suicide bombings from a north-eastern forest stronghold.
Some 13,000 people have been killed and 1.5 million driven from their homes in the nearly six-year-old uprising that spilled over Nigeria's north-eastern borders.