MAHWAH - State police say three cement company employees were killed in a crash on Route 287 in Mahwah Tuesday afternoon. 

The crash shut down the northbound lanes of Route 287 in Mahwah. Traffic was diverted at Exit 59, according to state police.

State police say a tractor-trailer struck a disabled cement mixer on the shoulder just after 12:30 p.m. The driver and two other men with Concrete on Demand in Oakland were outside trying to fix the vehicle at the time of the crash.

Investigators say the tractor-trailer, which was carrying a load of bricks, veered onto the shoulder and struck the mixer, the men and a Toyota Avalon.

The tractor-trailer cab and the sedan caught fire.

A husband and wife in the Toyota and the driver of the truck were treated for minor injuries, according to police. 

Police have not said whether the driver of the tractor-trailer will face charges. "Right now that's under investigation," says State Police Lt. Brian Polite. "The truck driver is at the hospital. He will be interviewed. We will get his statement as to the reasons why he couldn't stop."

Investigators say initial reports indicate traffic was slowing in the area at the time of the accident.

The victims have not yet been identified.