(CNN) -- The gunman who killed two others before police ended his life in a shootout near Texas A&M University had been battling mental health issues on and off for years, his mother said. Police say Thomas Caffall, known to his family as "Tres," killed a constable and a bystander and injured four others Monday before police fatally shot him. His mother, Linda Weaver, said the family became worried after Caffall quit his job in January and announced that he would never work again. 3 killed in shootings near Texas A&M "We had been very concerned about him," Weaver told CNN.
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NEW: The gunman apologized as he lay dying, a medic and witness says
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Police: Thomas Caffall was the gunman who killed two and injured four
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He was fatally shot by police in College Station, Texas
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Among the victims was Brian Bachmann, a highly regarded law enforcement officer
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