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HOUSTON (AP) — A law enforcement investigator dining at a Houston-area restaurant has fatally shot a gunman who opened fire at the eatery.

The Harris County Sheriff’s Office says the investigator escaped harm Sunday night.

Authorities say two people were involved in an argument inside the restaurant at a strip mall. A man walked outside to his vehicle, retrieved a handgun and fired several times through the glass front door.

An investigator with the Harris County Attorney’s Office, who was a customer witnessed the shooting, and pulled his service weapon and returned fire, striking the suspect. The gunman died at the scene.

The name of the man who died wasn’t immediately released.

Authorities are trying to determine what led to the original disturbance.

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