UPDATE: As of 3 p.m., the scene is clear, and traffic is flowing normally.
The Route 9 southbound lanes over the Edison Bridge, which spans the Raritan River and is a major thoroughfare to shore areas, are closed early Tuesday afternoon due to a crash.
The multi-vehicle crash involves at least one overturned vehicle, resulting in heavy delays, according to 511nj.org.
Numerous emergency vehicles are on the scene, according to JSHN contributor Kasey Leigh, who is sitting in the traffic shortly before 1 p.m.
Four people suffered minor injuries, according to a release from the Sayreville Police Department. Photos posted by police on Facebook indicate heavy damage to multiple vehicles.
Numerous tow trucks have been requested to the scene.
Police expect heavy residual traffic through the afternoon.