SAN ANTONIO -

On Christmas Day, a man dressed in women's clothing was caught trespassing on the tarmac at the Newark Liberty International Airport.

Later that day, Robert Edward Bump, 49, climbed over a fence and onto the runway of Phoenix Sky Harbor International Airport. Bump was arrested after banging on the engine of a Southwest Airlines plane.

"You wonder how they got out there," said airport guest, Andy Stone. "It's hard to get through here, relatively, you wonder how in the world did they get through the perimeter and get to an airplane like that," Stone said.

These incidents happened last week following years of beefed up security after 9-11.

"It's alarming. It makes you think they need to really look at their security outside as well as inside," Stone said.

A similar incident occurred at San Antonio International Airport in August.

William Ware, 22, was arrested after driving in the airport perimeter fence and accessing a restricted area of the airport, nearly hitting a parked aircraft.

"We have a layered approach when it comes to security. Not only do we have cameras, we have staff and we have the barbed wire fence," said Nora Castro, San Antonio International Airport public information officer. "These are layers in addition to other security measures that I can't get into."

The Defenders pointed out to Castro that despite the security measures, Bump and Ware were able to penetrate security.

"If you're asking if there's 100 percent proof if people won't get through the fence, our hope is that they won't," Castro said. "And with this layered security, we're hoping that if they do get through the fence, that we're able to apprehend them pretty quickly."

When asked by the Defenders if there have been changes following the security breach at San Antonio International Airport, Castro said, "I am not aware of what changes were made as a result of that incident."

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