Engineers Friday night were analyzing a steel fracture that forced the shutdown of the Delaware River Bridge, leaving thousands of evening commuters scrambling for alternative routes between the New Jersey and Pennsylvania Turnpikes.

The toll bridge will not reopen until the problem is clearly determined and repairs are completed, said Carl DeFebo, spokesman for the Pennsylvania Turnpike Commission.

The bridge, on I-276, connects Bristol Township on the Pennsylvania side to Burlington Township on the New Jersey side and handles 42,000 vehicles daily. It is jointly owned by the Turnpike Commission and the New Jersey Turnpike Authority.

Engineers for both agencies hope to announce this weekend an estimated timetable for repairs so motorists can plan for the work week, DeFebo said.

Inspectors were on the bridge Friday afternoon looking at a repainting project being performed by contractors hired by the Turnpike Authority when they discovered the fracture in a steel truss near the western shore of the Delaware, DeFebo said.

DeFebo said he did not know when the bridge was inspected last. Inspections are performed every two years.

"Keeping this bridge closed is the right decision for the safety of both our travelers and workers," said Pennsylvania Turnpike Chairman Sean Logan.

The bridge, which spans more than 6,500 feet from abutment to abutment, opened in 1956 after two years of construction.

No major repair projects for the bridge are in the pipeline, DeFebo said, but there has been a proposal to build a parallel span as part of the I-95 upgrade currently underway. If a second bridge is constructed, one would carry eastbound traffic and the other westbound traffic.

The bridge will be a vital roadway to a distribution center being built by Amazon.com in Burlington County.

The Pennsylvania Turnpike Commission advised motorists wanting to cross into New Jersey  to exit at the Bensalem Interchange, follow U.S. Route 1 north, to I-95 north, to I-295, south, to I-195 east. Take Exit 6 on I-195, and reenter the New Jersey Turnpike.

The New Jersey Turnpike Authority said alternatives for getting across the Delaware include I-78, I-295, and the Burlington-Bristol Bridge.