Updated

Suspicious bags led to brief shutdowns of an airport and major train station Monday, demonstrating the nation's heightened sensitivity to security threats on the fifth anniversary of the 9/11 terrorist attacks.

No genuine threats were found after the incidents in Long Beach and New York. An airliner flying from Atlanta to San Francisco was also diverted.

Authorities at Long Beach Airport blew up a suspicious package found in a rental car, airport spokeswoman Sharon Diggs-Jackson said. The airport was closed for about two hours.

The suspicious carrying case was destroyed as a precaution by a bomb squad.

"You never know what's in there, and you don't want to risk anybody's safety," said Sgt. Paul Patterson of the Los Angeles County Sheriff's Department.

Authorities in New York City briefly evacuated Pennsylvania Station and suspended all train service in and out of the busy hub because of a suspicious bag that later was determined to contain only trash.

The incident occurred minutes before a ceremony in lower Manhattan commemorating the terrorist attacks on the World Trade Center and as President Bush visited a firehouse whose members were among the first responders when the twin towers were hit.

In Long Beach, Anthony Gasparino, 31, was not upset that he had to wait 90 minutes to turn in his rental car before catching a flight to New York City.

"Not on Sept. 11," Gasparino said.

Elsewhere, a San Francisco-bound United Airlines plane was diverted to Dallas as a precaution after an unclaimed BlackBerry was found on board, federal authorities said.

Officials had also found and removed an unidentified backpack from the plane, Flight 351, before it left Atlanta, said Transportation Security Administration spokeswoman Yolanda Clark.

Flight 351 reached San Francisco International airport more than 2 1/2 hours late.