A crash on Interstate 280 involving a dump truck left several people injured, including three state troopers and five firefighters.

New Jersey State Police say that the troopers were on the eastbound side of the highway in West Orange around 10 a.m. Tuesday investigating a previous, unrelated car crash when the dump truck collided with the troopers and their vehicles.

Officials say that two of the troopers sustained serious injuries that are not considered life-threatening. Another trooper sustained minor injuries. Details of those injuries were not immediately released.

The President of the New Jersey Firefighters Mutual Benevolent Association, Ed Donnelly, says five West Orange firefighters were also hospitalized but are doing OK.

Part of his statement said: "I am happy to let you know all firefighters and state troopers are alive. Some are in very serious condition and will require a long road to recovery."

The eastbound side of I-280 was closed for about nine hours between exits 8 and 11. Those lanes have since reopened.

After the crash, the dump truck was seen lying partially on its side against the guardrail of the highway. The front of the dump truck was pushed up against the back of an ambulance, which was already at the scene for the previous crash.

It was not immediately clear why the driver of the dump truck was unable to avoid hitting the other cars.

The Associated Press wire services contributed to this report.