A man being escorted out of a Lewisville mall by security guards Monday afternoon pulled a gun and shot himself, police reported.The man was pronounced dead on arrival at a hospital, Capt. Kevin Deaver, a Lewisville police spokesman, said in a news release.No one else was hurt.Police were dispatched shortly after 4 p.m. to Vista Ridge Mall, 2401 S. Stemmons Freeway."A female was having a verbal argument with a male acquaintance," Deaver wrote. "Mall security arrived on the scene and began escorting him from the property."The person removed a handgun from his clothing and shot himself."He had not been identified by late Monday.