SUN PRAIRIE, WI (WTAQ) - A driver who died in a one-car crash just off a Dane County expressway has been identified as 53-year-old Frederick Smith of Madison.

A 28-year-old passenger, a man from Juneau, was treated at a hospital for minor injuries.

The mishap occurred Monday morning, just off the Highway 151 four-lane north of Sun Prairie.

Authorities said the car left an off-ramp, fell down an embankment, and rolled over several times.

Dane County sheriff’s deputies said speed and alcohol appeared to be factors, but they’re still investigating.