With help from the Allentown Fire Department, officers were able to convince the man to come back over the ledge of the 8th Street Bridge around 11 p.m., after nearly four hours on the scene, Allentown police said.
He was taken to an area hospital for treatment, police said.
Martin Luther King Jr. Boulevard was temporarily closed to eastbound and westbound traffic below the bridge.
No further information was available.
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