Karen Jean Christiansen, 67, and her daughter Jena Helene Christiansen, 32, died while traveling in Rosemount, Minnesota on Monday around 4:40 p.m.
On Wednesday night, the the Hennepin County Medical Examiner said the official cause of death for both was blunt force head trauma due to the crash. According to Rosemount Police, it took more than four firemen to roll the boulder at the scene.
"If you tried to duplicate this millions of times, I don't think you'd be able to do that. I think it was a very unique situation," said Rosemount Police Chief Mitchell Scott.
After the crash, authorities used business security cameras to capture a picture of the truck, which was a commercial vehicle. The driver of the truck was identified as Joe P. Czeck.
According to a press release, Czeck was arrested by Rosemount Police on Wednesday, July 11, and is currently being held in the Dakota County Jail.
"We had a connection like no other... my heart is broken... the world has lost an angel," Jena's boyfriend Ryan Kilian told KSTP.
Kilian said Jena worked as a general manager for several Red Lobster restaurants in the area.
According to KSTP, shortly before the accident, Karen met with former coworkers at Dakota County Technical College.
A family friend told KSTP, "Karen was a sweetheart of a lady."