MARSHALLTOWN, Iowa (AP) — Autopsies say two siblings and a cousin died while swimming in central Iowa during a Fourth of July outing with family and friends.

Marshalltown Police Chief Mike Tupper says 9-year-old Lee Meh, her 7-year-old brother, Sae Reh, and their 7-year-old cousin, Thay Mo, were found Wednesday night in the Iowa River.

The children became separated from others while swimming in the river in Marshalltown, about 50 miles northeast of Des Moines. Authorities searched for more than three hours before finding them.

Tupper says drought has left the river ankle deep in some places, but that pockets of 12-plus feet of water remain.

He says autopsies are scheduled for Thursday, but complete results won't be available for weeks.