A bomb exploded at a livestock market in the northeastern Nigerian city of Maiduguri on Tuesday, killing at least 50 people, according to a witness.
"We have been helping to evacuate the corpses and I can say over 50 people died from the attack," Isa Mohammed, a member of a vigilante group, said by phone.
It marked the latest in a string of attacks since Muhammadu Buhari was sworn in as president of Africa's biggest economy on May 29, vowing to defeat militants who have been fighting a six-year insurgency to establish Islamic law. At least 26 people died on May 30 in Maiduguri, the capital of Borno state, when a suicide bomber blew himself up at a mosque.