"Aviation experts call it a miracle," says Honolulu's KHON-TV. "The FBI says a 16-year-old boy stowed away in the wheel well of a flight from California to Hawaii, and survived. The boy is expected to fully recover."

Update at 11:33 p.m. EDT: The AP is now saying the boy is 15, not 16, as was earlier reported.

Our original report continues:

According to The Maui News, the unidentified teen survived the trip "halfway across the Pacific Ocean unharmed despite frigid temperatures at 38,000 feet and a lack of oxygen, FBI and airline officials said."

The Associated Press writes that FBI spokesman Tom Simon says the "kid's lucky to be alive." The news service adds:

"Simon said security footage from the San Jose airport verified that the boy from Santa Clara, Calif., hopped a fence to get to Hawaiian Airlines Flight 45 on Sunday morning. The child had run away from his family after an argument, Simon said. Simon said when the flight landed in Maui, the boy hopped down from the wheel well and started wandering around the airport grounds." 'He was unconscious for the lion's share of the flight,' Simon said. The flight lasted about 5 1/2 hours."

KHON spoke with airlines analyst Peter Forman, who said:

"The odds of a person surviving that long of a flight at that altitude are very remote, actually. I mean, you are talking about altitudes that are well above the altitude of Mount Everest. And temperatures that can reach 40 degrees below zero. A lot of people would only have useful consciousness for a minute or two at that altitude. For somebody to survive multiple hours with that lack of oxygen and that cold is just miraculous. I've never heard of anything like that before."

The boy, Simon told the AP, has been handed over to child protective services in Hawaii and will not be charged with a crime. The jet he reportedly stowed away on was a Boeing 767.

In California, the wire service adds, "a Mineta San Jose International Airport spokeswoman said airport police were working with the FBI and the Transportation Security Agency to review security at the facility as part of an investigation."

U.S. Rep. Eric Swalwell, a Democrat whose district includes cities and suburbs east of the San Francisco Bay Area and who serves on the Committee on Homeland Security, tweeted Monday that he has "long been concerned about security at our airport perimeters. #Stowaway teen demonstrates vulnerabilities that need to be addressed."

Update at 11 a.m. ET. More On How Incredible This Seems:

"Some experts theorized that because of the unforgiving conditions, the boy's body went into a state of hibernation, remaining unconscious until the plane reached a lower altitude," The San Francisco Chronicle writes. [It's] 'a medical miracle, akin to those who fall into frozen rivers and survive,' said former San Francisco International Airport spokesman Michael McCarron."

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