Security heightened at airports nationwide for anniversary of killing of Osama bin Laden

SAN DIEGO - Security is expected to be heightened at airports nationwide today, including Lindbergh Field, for the one-year anniversary of the killing of al-Qaida leader Osama bin Laden.

In advance of the anniversary, security has been stepped up at airports in Europe and the Middle East, and federal air marshals have been deployed overseas, according to various reports out of Washington, D.C.

U.S. and European authorities have been warning for the past year that al-Qaida operatives were working to design non-metal explosives that can be surgically implanted so a suicide bomber could get through airport security.

Still, officials with the U.S. Department of Homeland Security insisted that they had seen no strong evidence of an impending terror strike.

''We have no indication of any specific, credible threats or plots against the U.S. tied to the one-year anniversary of bin Laden's death,'' DHS spokesman Peter Boogaard told ABC News.