The shootings, which also injured several people, occurred about 2 p.m. Wednesday at the market in Maiduguri, witnesses told the Nigerian Tribune.
Elsewhere in the capital, a mechanic was fatally shot Wednesday afternoon, the Tribune said.
The Joint Military Task Force said three terrorists were killed by authorities Tuesday in the northern state of Kano after they had stolen a car at gunpoint.
Nigerian Army Maj. Gen. Garba Ayodeji Wahab said the gunmen had planned an attack this week in the northern state of Kano.
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