The double-shooting of Australian twin sisters that left one of the women dead was a suicide pact, investigators said Thursday after interviewing the surviving sister.
The 29-year-old sisters, who have not been identified, had been in the Denver area for about five weeks before going to a shooting range Monday, the Arapahoe County sheriff's office said.
Capt. Louie Perea said the surviving sister told officials that the two planned to commit suicide together and that the two shot themselves at the range. He said physical evidence and video surveillance footage backs up that claim.
It wasn't immediately known why the women decided to commit suicide.
Surveillance video at the range captured the sisters falling out of the stall about a halfsecond apart, with patrons quickly reacting.
The women are from Victoria state in southeast Australia and the women's relatives are set to arrive in Colorado on Friday afternoon.
It's not clear what the women were doing in the United States.