There was no claim of responsibility for the attack – the first of its kind on Yola – but it bore the hallmarks of militant group Boko Haram.
Police in the Adamawa state capital Yola said two assailants approached the Jimeta Main Market on Thursday and faked a fight to attract victims before blowing themselves up.
“Ten more people died this morning,” police spokesman Othman Abubakar said, adding to the 35 bodies that a senior policeman earlier said he had seen at the bomb scene. Around 40 people were wounded, said Mr Abubakar.
Boko Haram has waged a six-year insurgency to try to set up a “caliphate” in the north-east of Africa’s biggest oil exporting country, but government counteroffensives this year have retaken much of the territory held by the extremists.
However, bomb attacks have resurged since the inauguration of newly elected president Muhammadu Buhari last week, with 80 people killed in a series of attacks over the past few days.
“I can see blood splattered everywhere, including my car, but I can’t give any detail because we are all running,” bread seller Ayuba Dan Mallam said shortly after the blasts in Yola.
The explosion was timed to go off as merchants were closing shop, others were hurrying to make last-minute purchases and commuters were catching tricycle taxis home.
The local government has blamed the attack on Boko Haram. Yola has had its population double with some 300,000 refugees fleeing the insurgent violence in the north-east that has killed some 13,000 people and forced 1.5 million from their homes.
Two hours earlier, eight soldiers were killed by a suicide car bomb at a checkpoint outside a military barracks in Maiduguri, the biggest city in the north-east and the centre of the conflict some 410 kilometres north-east of Yola.
In his inaugural speech, Mr Buhari – a Muslim – promised to eradicate the “mindless, godless” group and rescue hundreds of women and children held captive by the militants, including 200 girls taken from the town of Chibok a year ago.
The violence on Thursday came as Mr Buhari ended his first foreign trip since taking office.
He had been in Chad’s capital N’Djamena on Thursday for talks with his counterpart Idriss Deby after visiting Niger on Wednesday.
“Your troops have stood shoulder to shoulder and fought gallantly with ours in the fight against the forces of evil,” the 72-year-old former military ruler told Mr Deby.
For his part, Mr Deby “reaffirmed Chad’s involvement and availability” to work with Nigeria.
Anglophone Nigeria has typically viewed its francophone neighbours with suspicion, which has been blamed for the lack of a joined-up approach in tackling the militants.
The head of the Africa Programme at the London-based think tank Chatham House, Alex Vines, said the trip underscored the fact that Mr Buhari “needs to make quick progress on Boko Haram ... and needs the support of Chad and Niger”.
If Nigeria’s president meets early setbacks against the insurgents, it could undermine his ability to push through “tricky reforms”, including expected anti-corruption measures, he added.
“Progress in (the) north-east will help strengthen support for his mandate, which will be important,” he said.
On Wednesday, the military in Abuja announced that a Nigerian officer had taken charge of the new African Union-backed Multi-National Joint Task Force based in N’Djamena.
The 8,700-strong unit, made up of military personnel, police and civilians from Nigeria, Niger, Chad and Cameroon, had been due to be deployed last November.
Mr Buhari has ordered the military’s command centre be moved from Abuja to Maiduguri, where Boko Haram was founded in 2002.
* Reuters, Associated Press, Agence France-Presse