The tractor trailer struck the van in the drivers side. Unfortunately the driver was killed on the scene from the impact.

[The van] couldn't avoid hitting the tractor-trailer, ... Their brakes locked up.

This roadway here has actually a lot of curves. What ended up happening, the driver ended up not being able to negotiate one of the curves and actually ended up over steering to the left, causing the vehicle to lose control.

For unknown reasons she pulled into the path of of a semi-tractor-trailer and was struck and it spun her vehicle around and the vehicle was then hit by a second semi-tractor-trailer,

All of that is part of the investigation, which is ongoing.

It happens from time to time, but it's not very common.