CROOKSTON - A father and son were killed in plane crash north of Valentine in South Dakota last Sunday.

KNOP News 2 reports that officials say they don't have a cause or exact time of the crash yet, but they do know the plane was found in a prairie between Saint Francis, South Dakota and North of Crookston, Nebraska.

Officials say Clint Vanderwey and his son Jed Vanderwey of rural Crookston died in the crash.

The National Transportation Safety Board is investigating the incident.