The hazardous material team prepare to enter the Art Culture and Technology building at University of California, Irvine, Wednesday, Jan. 6, 2010, in Irvine, Calif. Investigators are probing a fifth suspicious letter containing a white powder found on the campus. The powder was determined to be harmless in the other four instances. (AP Photo/The Orange County Register, Cindy Yamanaka) LA TIMES OUT. MAGS OUT. NO SALES.