The Glacier County Sheriff's Office has identified the people who were killed and injured and the person suspected of the crimes on Sunday near Glacier National Park.
Sheriff Vernon Billedeaux said in a news release that at about 8:56 p.m. the dispatch center received reports of a man shooting at a woman in East Glacier Park. Several law enforcement agencies responded to the scene where they found two dead men, two critically injured women, and a critically injured toddler.
Billedeaux said the initial investigation determined the suspect, 37-year-old Derick Amos Madden of Oklahoma, deliberately drove his vehicle into a group of people who were walking beside the road. Madden then crashed his vehicle into a tree, got out of the vehicle with a shotgun, and began shooting at the people he had just hit or tried to hit with his vehicle.
Madden shot and killed 39-year-old David Siau of Syracuse, New York. Madden continued shooting at the people who were running away, hitting and wounding Christy Siau, 40, and McKenzie Siau, 18 months. Both were also from Syracuse.
Madden then attacked Christina Siau, 30, of East Glacier Park, with a knife. Billedeaux said Christina Siau "fought for her life and despite receiving critical injuries, fatally wounded Madden who died at the scene."
Two minor children were also present but were able to run away and were not injured.
Christy Siau, Christina Siau, and McKenzie Siau were taken to the Indian Health Service clinic in Browning, where the toddler was pronounced dead.
The women were airlifted to hospitals to receive more advanced care and their medical conditions have not been disclosed.
Billedieaux said the investigation determined that Madden had been in a prior relationship with Christina Siau, and suffered from mental health issues.
The investigation continues and detectives are working to gather and analyze all details and circumstances.
Bethany Siau, the sister of David, has created a GoFundMe.