Harry James McCullough took it personally. The former security guard was standing at a Walgreens checkout counter when he saw two masked men, one with a sawed-off shotgun, enter the store. Marquail Thomas, 18, pointed the shotgun at customers and yelled, “Nobody (expletive) move!'' “There's no doubt in my mind what they were going to do,” McCullough said Thursday. “There was no time to react. You only have one chance.” McCullough pulled out a pistol and shot Thomas four times. Thomas collapsed outside the store and died later at a hospital. McCullough chased down the second masked man, whom Omaha...
