SAN DIEGO (AP) - An untold number of so-called zombies are headed for a counterterrorism summit attended by hundreds of Marines, Navy special ops, soldiers, police, firefighters and others to prepare them for their worst nightmares.

The president of San Diego-based security firm Halo Corp, which is hosting the Oct. 31 training demonstration during the summit, says it's a "very real exercise," not "some type of big costume party."

Hundreds of military, law enforcement and medical personnel will observe the Hollywood-style production of a zombie attack as part of their emergency response training.

Called "Zombie Apocalypse," the exercise follows the federal Centers for Disease Control and Prevention's campaign launched last year that urged Americans to get ready for a zombie apocalypse, as part of a public health message about the importance of emergency preparedness.

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