All lanes are back open after a fatal crash caused major backups on northbound Interstate 5 near Bow Hill Road just north of Burlington Friday evening.

The right lane opened to traffic at 6:35 p.m., and the left lane opened about 8 p.m.

At one point there was a four-mile back-up, according to WSP.

A car driving southbound on I-5 had crossed the grass median and collided with a box truck that was driving northbound, according to Washington State Patrol.

The driver that was in the southbound vehicle died, WSP said.

It is not known why the vehicle crossed the median.