A man is under arrest for killing his parents outside of his Northwest Side apartment. The shooting happened Sunday at an apartment complex on Parkdale near I-10. An officer was working a traffic accident nearby when he heard gunshots. When he went to check it out, he found a man and a woman in their 40s or 50s, shot to death outside a first-floor apartment. He saw a man later identified as 20-year-old Michael Burger holding a rifle and a shotgun. The officer arrested Burger on a charge of capital murder.