MAIDUGURI, Nigeria — A double suicide bombing at a market in Nigeria’s northern city of Maiduguri killed at least 12 people and wounded 48 others on Wednesday, residents and an emergency official said.

Ibrahim Usman, a trader in the Muna Garage market, said the first bomber attacked inside the market while the other remained outside, killing only himself.

“Suddenly there was a loud bang and everywhere became disorganized,” Mr. Usman said. “I counted 12 corpses and over 40 injured victims.”

The official in charge of rescue operations for the State Emergency Management Agency, Bello Dambatta, said that the bomber who was inside the market was a woman and that the one who remained outside was a man.