One person was killed and another injured in a semi accident in Allamakee County.

The crash happened Wednesday around 5 PM about four miles north of Monona.

According to the Iowa State Patrol, 60-year-old Algie Crowder of St. Francis, Ark., drove off the pavement of County Road X-26 (Volney Road) and went into a ravine. Crowder and the semi's passenger, 40-year-old Sandra Davis McDowell, also of St. Francis, Ark., were both ejected from the rig.

The Iowa State Patrol said Crowder was killed in the accident. Davis-McDowell was airlifted to a La Crosse, Wis., hospital for treatment of undisclosed injuries.

Authorities are trying to figure out why Crowder left the highway. The accident remains under investigation.

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