American Airlines Terminal 8 was evacuated and shut down after the bag was discovered just after 7:30 a.m., said Steve Coleman, a spokesman for the Port Authority of New York and New Jersey, which runs the airport. The terminal reopened at 9 a.m.

The rest of the airport stayed open while the bag was checked.

The black briefcase-type bag apparently had almost nothing in it, Coleman said. The bag’s owner was en route to San Francisco, Coleman said.

"Out of an abundance of caution, the check-in area and security checkpoints were closed," the Transportation Security Administration said in a statement.

A Port Authority police K-9 unit and an NYPD bomb squad responded. Police "determined the item and its contents were not harmful," American Airlines said in a statement.