Both levels of the George Washington Bridge were temporarily closed to traffic on Thursday night after a suspicious package was discovered on the span connecting New York and New Jersey, the authorities said.

The New York Police Department’s bomb squad removed an empty cylinder from the New Jersey side of the upper level, the authorities said.

The episode began around 9:30 p.m., with the upper level shut down for police activity, followed by the lower level.

The police did a sweep of the eastbound lanes of the upper level before the span reopened. Both levels were reopened to traffic by 11:30 p.m., the Port Authority of New York and New Jersey said.