The search for the man began shortly before 6 a.m. Monday in the Juniata section of the city.
Emergency personnel used shovels, rakes, and ladders to remove trash from the truck while they tried to locate the man.
Once they found the man still alive, it took close to two hours to reach him and pull him out of the dumpster.
He was placed on a stretcher. His condition has not been released.
It is not clear at this time how crews discovered a man was trapped inside the truck.
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