United Airlines is now looking into why a commercial flight had to land at Dover Air Force Base.
The aircraft touched down at around 7:30 p.m. on Monday night about an hour after it took off from Newark.
It was bound for Palm Beach.
WBOC reports that the airline said there was a mechanical problem but did not specify what that was.
The passengers eventually arrived in Palm Beach on a different flight.
Col. Corey Simmons, Vice Commander of the 436th Air Lift Wing, told the television station that the situation was unusual and serious.