The truck crashed into a barrier and caught fire on Route 3 West near Valley Road and Grove Street at around 9:07 a.m. on Monday, July 22, Passaic County Prosecutor Camelia Valdes said in a news release.
The 55-year-old man's body was found after Clifton firefighters put out the flames.
Route 3 is closed in both directions for several hours as emergency crews remain at the scene. The state Department of Transportation said evening rush hour drivers should take alternate routes to avoid delays.
Clifton police said some nearby homes were evacuated as a precaution. Social media videos showed heavy smoke and large flames coming from the 18-wheeler.
The Little Falls Police Department said officers and firefighters were assisting Clifton first responders.
Anyone with information about the crash should call the Passaic County Prosecutor's Office at 1-877-370-7276.
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