A man gets some rest inside the Agri-Plex at the Allentown Fairgrounds after being evacuated from her building when an explosion rocked the intersection of 13th and Allen Streets in Allentown, Pa., early Thursday Feb. 10, 2011. Fire Chief Robert Scheirer said the cause of the explosion was unknown but natural gas from a ruptured underground line was feeding the fire. He said eight houses were destroyed and about 500 people evacuated, including elderly residents of a high rise. Several buildings are involved and at least two people are still unaccounted for. (AP Photo/Rich Schultz)