A 20-year-old Baltimore County man was seriously injured early today when he fell off the CSX railroad bridge over the Gunpowder River after he lost control of an all-terrain vehicle.

The victim, Christopher W. Milan of Shipley Lane in Kingsville, was with another man at 4:20 a.m. when he lost his balance and fell more than 60 feet in the 12400 block of Pulaski Highway, in Harford County.

The companion ran to a nearby house and reported the incident, said a spokesman for the Harford County Sheriff's Department.

Milan was in serious condition at the Shock-Trauma Unit in Baltimore with possible internal injuries.