The wreck happened at 4:41 a.m., New Jersey State Police report.
An overturned dump truck was slowing the morning commute on Interstate 80 East in Allamuchy Township, according to the New Jersey Department of Transportation.
The left lane remained closed after 7 a.m. following the 4:41 a.m. incident, the DOT and New Jersey State Police said.
The truck was the only vehicle involved in the crash and it wasn't immediately clear if there were injuries, according to police at the Hope barracks.
Delays were 30 to 40 minutes, the DOT said. The crash is just east of the rest area, the DOT said. The cleanup was continuing at 7:25 a.m., police said.
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