Last update: 6:03 p.m. Saturday

A truck driver was killed when the tractor trailer he was in crashed into an office complex, burst into flames and ignited the building on Route 17 in Hasbrouck Heights Saturday morning, authorities at the scene said.

Hasbrouck Heights Police Detective Alan Baker said witnesses reported seeing the tractor trailer veer across two lanes before striking the north side of the building at 500 Route 17 South, near the intersection of Williams Avenue at around 6:45 a.m.

The truck did not strike the building head-on, he said, but wrapped around the columns. The driver was found dead in the cab, authorities said. The charred remains of truck's cab was wedged under the building, in a parking area.

The truck's fuel tank ruptured after impact, sparking the fire and causing heavy damage to the building, Heights Fire Chief Richard Giarrantana said from the scene. There does not appear to be major any structural damage to the office from the third-alarm fire, he said. 

It took firefighters 25 minutes to knock down the blaze, the chief said. Fire crews from towns including Wallington, Lodi and Carlstadt responded to the blaze. The Teaneck Fire Department's Box 54 Unit was also called in.

"It was like an inferno," nearby resident Angela Roache said. "I was in the kitchen and I heard a big blast." 

Roache said the flames were out by the time she walked to the scene.

"The front of the truck was all burnt out," she said. 

The office complex, which houses local offices for the federal Occupational Safety and Health Administration (OSHA), was empty when the tractor trailer struck, authorities said. 

"OSHA staff from that office will telework Monday, but in general normal agency operations will not be interrupted," agency spokesman Jesse Lawder said in an e-mail. 

It remains unclear what caused the accident, according to Heights police. Detectives on scene said there did not appear to be any large skid marks to indicate braking.

The truck appeared to be full of office supplies and not hazardous materials, Baker said. Numerous agencies were on scene investigating, including the County Hazmat unit and the NJ Department of Environmental Protection (NJDEP).

The trailer is owned by Land Air Express of New England, which has an office in Carlstadt. It's unclear what company owns the cab, however, according to police. Representatives for Land Air Express could not immediately be reached for comment.

Sgt. Nicholas Sisto said the driver has been identified and authorities are reaching out to the family for notification prior to publicly releasing the name.

Traffic on Route 17 S had initially been closed but reopened by Saturday afternoon.

Check back for more updates on this breaking news story.