The gunman who shot multiple people at a high school in Iowa on Thursday is dead, according to multiple media reports.

The Associated Press, citing a law enforcement official who was not authorized to speak publicly on the investigation, reported that authorities believe the shooter died from a self-inflicted gunshot wound.

Dallas County Sheriff Adam Infante said at a news conference that the incident occurred at 7:37 a.m., before classes at Perry High School began. Deputies were on scene within seven minutes. He said there were “multiple gunshot victims,” but that it’s “still unclear exactly how many are injured and what the extent of those are.”