(CNN) The volunteer security team member who fatally shot a gunman in a Texas church Sunday said he began watching the shooter as soon as he entered the sanctuary.

Jack Wilson, head of security at West Freeway Church of Christ in White Settlement, told CNN affiliate KTVT that he had "eyes" on the man right away.

Jack Wilson

"After he shot (the two victims), he went and started towards the front of the sanctuary and that's when I was able to engage him, and I fired one round," he told KTVT.

Wilson didn't say why he was suspicious, but another parishioner told KTVT the man's appearance made her uncomfortable because he appeared to be wearing a wig.

Wilson, who is running for county commissioner in Hood County, posted a statement on his campaign website thanking "all who have sent their prayers and comments on the events of today."

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