Toddler and her father killed after man uses vehicle to mow down family outside Montana national park

Two people, including a toddler, were killed after a man plowed his vehicle into a family walking near a Montana national park and then opened fire with a shotgun.

The suspect was identified on Tuesday as 37-year-old Derick Madden from Goldsby, Okla. Authorities said he had “mental health issues” and was previously in a relationship with one of the victims injured in the attack.

The chaos unfolded Sunday night in the small village of East Glacier Park, just outside Glacier National Park on the Blackfeet Indian Reservation, according to the Glacier County Sheriff’s Office. The Siau family, on vacation at the time, were strolling along a small road near the entrance when Madden raced toward them around 9 p.m., striking several members of the group before crashing his vehicle into a nearby tree.

As the family attempted to flee, Madden pulled out a gun and opened fire.

David Siau, 39, was killed in the shooting and his 40-year-old wife Christy Siau was critically injured. At the time, she’d been holding their 18-month-old daughter, McKenzie Siau, who later died from her injuries at the Indian Health Service hospital.

Christina Siau, David’s sister, was also hurt. Authorities said she was once in a relationship with Madden.

Another two children were present during the attack, but managed to escape without injury, the Glacier County Sheriff’s Office said.

“The attack was isolated to this incident with a clear nexus between the victims and Madden,” according to authorities.

“The investigation continues and detectives are working tirelessly to find all the details and circumstances surrounding this horrific event.”