A January school shooting at Perry High School near Des Moines, Iowa, which left two dead and six injured, was “the product of significant preparation and planning,” by a lone shooter, a new report released by the Dallas County Attorney’s office found.

The shooter responsible for two deaths and multiple injuries at an Iowa high school earlier this year “likely displayed warning signs” according to a detailed report from state officials released

The student gunman in a small-town Iowa school shooting in January in which two people were killed and several others injured was known to have a fascination with school shooters and exhibited a number of unreported “warning signs,