A 59-year-old Ypsilanti man died in a crash Sunday night on North Huron River Drive in Ypsilanti Township, Washtenaw County sheriff's deputies said.

The man was traveling west in a 1998 Chevrolet van that went off the right side of the road, over a curb, hit a small tree and slid on its side into a large tree, sheriff's department spokesman Derrick Jackson said.

The man was pronounced dead at the scene of the 5:26 p.m. accident that occurred east of North Hewitt Road, Ypsilanti Township Fire Chief Eric Copeland said. Authorities have not released the driver's name.

The crash remains under investigation, but deputies suspect the driver may have lost control because of a medical problem.