Authorities continue to investigate how and when a fatal motorcycle accident occurred in Des Moines County. Late Wednesday afternoon a truck driver saw a motorcycle in a drainage ditch off County road 99 a mile north of the intersection with the Mediapolis Road. Branden Behne age 32 of Burlington was pronounced dead at the scene. Shawn Engle, age 25, also of Burlington, was airlifted to University Hospitals in Iowa City. Authorities believe the cycle was northbound at a high rate of speed when it left the roadway.