State officials breathed a sigh of relief when a tractor-trailer truck wreck on a St. Louis interstate was determined to be an accident, not an act of terrorism. Still, they say the wreck of a Federal Express truck on I-270 that scattered packages across the interstate and backed up traffic for hours provided a good test for homeland security efforts. State Homeland Security advisor Tim Daniel says he acted quickly after being notified about the accident that at first appeared to resemble an act of terrorism. He notified the governor’s office, then the White House. Daniel says the biggest problem was losing contact with emergency personnel at the scene who could give him better information. Investigators ruled out terrorism as they determined a guard rail ripped open the gas tank, causing it to catch fire, making it appear the trailer exploded.