Christopher Shell started the celebration of his 29th birthday as a passenger of US Airways Flight 1267. He then became a suspect in an investigation of explosives on board the Philadelphia-to-Dallas flight, but was later cleared as a victim of the hoax. Yet the Philadelphia man may still wind up in jail from charges based on unrelated outstanding warrants.

Flight 1267 was ordered back to Philadelphia as it flew over Harrisburg, Pa., as a SWAT team stormed the plane in Philly around 8:30 a.m., removing Shell from the aircraft and confiscating his carry-on luggage, the Philadelphia Daily News reported. The order was preceded by an anonymous call at around 7:30 a.m. from a person who said a passenger on the flight was carrying liquid explosives.

"He was obviously very alarmed as I would be if heavily armed police officers entered a plane to take me off," Joe Sullivan, the airport's chief inspector, told the Philadelphia Daily News. "He was certainly stunned."

A passenger on the flight, Steve McNeal of Pennsylvania, described Shell's demeanor as authorities closed in on him.

"He was just as surprised as I was," McNeal told NBC Dallas-Fort Worth. "He was just sitting there, looking straight forward. He was kind of, 'What's going on?' He had no clue."

It turned out Shell was the victim of a hoax and no bombs were found on the plane. Authorities said Shell was safe to continue his journey to Dallas.

"All indications are this was a hoax and a pretty nasty trick was played on a passenger, and it resulted in a threat to, really, all of the passengers," Sullivan told the Daily News.

Shell's ex-girlfriend and her current boyfriend are being questioned in the explosives hoax case, according to NBC Dallas-Fort Worth. The boyfriend is expected to be charged, the station reported, while Shell's former girlfriend is expected to be released in the case.

While Shell thought his involvement with authorities was over, that turned out not to be the case.

The Philadelphia man and former Fort Worth resident was arrested on outstanding warrants at the Dallas-Fort Worth airport, airport spokesman David Magana told Fox News. Magana told the news outlet that the warrants were from authorities in north Texas but did not go into specifics.

Sullivan noted to the Daily News that everyone on board the flight was safe and first responders rushing to the scene did not suffer any injuries on their way to the explosives threat.

 "It certainly was a very harrowing day for the gentleman and the passengers," he told the paper. "And it certainly was an expensive day."