Mexican authorities say eight people including a 13-year-old girl were killed in a string of shootouts between gunmen and security forces that caused panic in the border city of Matamoros.

A Tamaulipas state government statement says seven of those killed Sunday in the city across from Brownsville, Texas, were presumed criminals.

The girl was a bystander at a shopping mall with her family during one of the shootings. The statement said she was struck by a bullet fired by one of the suspects.

The violence began in the afternoon with a traffic stop in which the occupants of an SUV with Texas license plates allegedly opened fire on authorities. Three suspects were killed.

That unleashed a series of chases, roadblocks and shootouts in which the other victims died.