A car bomb exploded near a marketplace in northeastern Nigeria on Tuesday, killing at least 50 people.
The explosion was at a crossing in the city of Maiduguri in Borno state.
Local media report the market was crowded at the time and that many people were wounded.
The explosives were reportedly hidden under a load of charcoal in the vehicle.
Nigeria's security authority is investigating the incident as an act of terrorism.
The Islamic extremist group Boko Haram kidnapped more than 200 schoolgirls in the state in April.
On Sunday, a group believed to be members of Boko Haram attacked Christian churches and other targets, killing dozens of people.
No one has claimed responsibility for the latest explosion. But security officials say they believe Boko Haram is behind the attack.
Jul. 2, 2014 - Updated 03:39 UTC