Houston druggist slainHOUSTON (UPI) - A druggist who pulled a gun on armed bandits was shot to death Monday. Police arrested three men, one charged with murder, and sought a fourth.Don Hatchell, 39, pulled a gun from behind a drug counter and exchanged shots with (Hie of two bandits who entered his store about 11:30 a.m., Detective Bob Minerich said. A bullet struck Hatchell in the heart and he died at the scene.Police later arrested William Evans Horne, 23, at a hospital where he was being treated for bullet wounds in the arm and groin. He was charged with murder.Officers said two other men were being held. A fourth suspect remained at large.