Threat of Terror?

According to the P-G, an abandon briefcase left outside Molly Brannigan's was blown up by the Allegheny County bomb squad on Sunday. I'd be interested to learn whether there was a perceived terror threat, or was this merely standard operating procedure for the authorities?

UPDATE: The Trib has more coverage of the incident. Though it is still not clear why the briefcase was perceived to be a threat, or who notified the police of its presence on Washington Rd? Is this a case of overreaction? I am inclined to think so, but it's all mere speculation until we get more information.