FORT LEE, N.J. — Motorists are facing delays because crews are cleaning up a fuel spill caused by a jackknifed tractor-trailer on the George Washington Bridge.

One lane on the upper level of the span is open heading into New Jersey. Three other lanes are closed.

Friday’s accident occurred just before a former Port Authority of New York and New Jersey official who pleaded guilty in the criminal case about lane closures of the bridge took the stand in the trial of two former allies of Republican New Jersey Gov. Chris Christie.

David Wildstein pleaded guilty last year to orchestrating traffic jams in 2013 on the George Washington Bridge to punish a Democratic mayor who didn’t endorse Christie. Christie wasn’t charged.