TOLUCA, Mexico - A state security official says a street shootout possibly between local drug gangs has killed seven people and injured one in suburban Mexico City.

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Mexico state security agency spokesman Edgar Sanchez says the shooting occurred early Sunday morning in the northern part of Mexico state that borders Mexico City. He said the dead, six men and one woman, all suffered gunshot wounds, and none have yet to be claimed by family.

State Attorney General spokesman Alfredo Albiter said an investigation is under way on the cause of the killings, but he wouldn't discount a dispute between local street dealers.

A shooting between two suspected drug gangs killed eight in the same area last month.