SAN ANTONIO — The Bexar County Sheriff's Office is training first responders for the worst-case scenario.

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Its active shooter course trains responders to neutralize a suspect and help people who are hurt. Each responder uses a computer simulator that places them in the middle of the action. During the exercise, responders practice working together and with other agencies.

"Everybody learns from everybody else's mistakes, because if you make a mistake in a training environment it costs no life, no equipment. We can repeat and we can learn from it," said Deputy Chief Harry Jimenez.

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"In real life, it can cost someone's life."

Several agencies outside of San Antonio are also taking part in the 3-day training course.