Authorities say preliminary autopsy results show drowning as the cause of death for three North Dakota college softball players found dead inside a sport utility vehicle that sunk in a rural farm pond.

Stark County Sheriff Clarence Tuhy said Friday that two of the women's bodies were found in the SUV's rear cargo area and one was found in the middle of the vehicle.

The bodies of 22-year-old Kyrstin Gemar of San Diego, Calif.; 20-year-old Afton Williamson of Lake Elsinore, Calif.; and 21-year-old Ashley Neufeld, of Brandon, Manitoba, were found Tuesday.

Investigators believe the Dickinson State students were on a stargazing trip Sunday and likely drove into the water in the darkness.

A complete autopsy report, including tests for drugs and alcohol, isn't expected for a week or two.