Cameras zoomed in on the man, revealing that he had a handgun tucked into his shorts.
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Before the 2015 season, MLB bolstered its security measures, adding metal detectors in all 30 stadiums. Texas residents can obtain a license to carry a concealed handgun, it is illegal to do so at professional or amateur sporting events.
But as it turns out, the man was a police officer in plain clothes, one of the several thousand who were on-hand Monday to help support the son of slain Houston officer Richard Martin.
Good on the Astros for helping the local police force honor a fallen member. It is also reassuring that this was not a major security gaffe.