SAN JOSE (CBS 5) – A masked man’s recent visit to a San Jose post office led to a response by the bomb squad. But the student at the center of Tuesday’s bomb scare has an explanation for his attire.

The first reports were unnerving: a man wearing a mask stuffed a package into a mailbox at the busiest post office in San Jose Tuesday afternoon.

The bomb squad, firefighters, and the postal inspector closed down nearby streets. After four hours, a robot blew up the package, which turned out not to be dangerous.

Which begs the question: what about the man in the mask?

His name is Long Hoang, a 29-year-old nursing student and fitness buff. Hoang was on a so-called “crossfit” workout, a relatively new exercise regimen.

According to Hoang, the mask he wore was designed to restrict breathing to simulate training at high altitude. A vest he also wore to the post office was packed with ten pounds of weights.

CBS 5 asked Hoang if he could see how his workout gear could be scary to people. “Yeah,” he responded. “But when I’m in my little zone, and I’m just running and doing my thing, it wasn’t put into context.”

Long said he had to mail a package Tuesday. He put on his workout gear and jogged to the post office a few blocks away. Adding to the suspicion, the package didn’t easily fit into the mailbox.

Long turned himself into authorities Tuesday night. Police say he saved everyone hours of detective work.

“Totally big misunderstanding, totally unintended on my part,” Hoang said. “I won’t do anything like this ever again.”

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