MANITOWOC, Wis. — A 21-year-old Manitowoc man has pleaded not guilty to driving drunk and under the influence of drugs in a car crash that killed two people and injured four others.

Authorities say Dylan Karnitz was speeding when he crashed into a car in Manitowoc in March, killing 23-year-old Christopher Mark and 24-year-old Zachary Gates. A passenger in the victims' vehicle was seriously injured. Three passengers in Karnitz's Cadillac were treated at area hospitals and released.

HTR Media ( ) says Karnitz pleaded not guilty to 18 charges in Manitowoc County Circuit Court Tuesday, including two counts of homicide by intoxicated use of a vehicle.

Karnitz remains in jail on $15,000 cash bail.