A tractor-trailer driver from Alden died Thursday after he drove off the Thruway in Genesee County, State Police said.
At about 12:15 p.m., William W. Frank, 46, drove off the shoulder of the westbound Thruway into a heavily wooded area between exits 47 and 48 in Stafford, police said.
Frank, ejected from the rig, died at the scene.
Investigators don't know what made Frank drive off the highway. No other vehicles were involved in the crash.
The State Police Commercial Vehicle Enforcement Unit continues to investigate.