MOORHEAD, Minn. (AP) — The father of two teenage brothers from Moorhead who died in a rollover crash in June 2015 has filed a wrongful death lawsuit.

Ray Kvalvog says the lawsuit is about finding answers, and that he’ll donate any money he might win to charity.

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The Interstate 94 crash near Dalton killed 18-year-old Zach Kvalvog and his 14-year-old brother, Connor, while they and two other boys were heading to a basketball camp in Wisconsin. The Minnesota State Patrol a year ago said a semitrailer was the probable cause of the crash, but the truck hasn’t been found.

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Kvalvog’s lawsuit is against the teens’ school, their basketball coach, the maker of their sons’ pickup and their auto insurance provider, who all deny the claims.

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