Three girls and a woman were killed on Saturday morning when a truck driven by a Wisconsin man struck them as their Girl Scout troop was picking up trash along a roadway.
Another girl was injured and is in critical condition, the Lake Hallie Police Department said.
The driver of a black Ford F-150 pickup fled but turned himself in later.
Police identified him as Colton Treu, 21, of Chippewa Falls.
“The Lake Hallie Police Department would like to extend our deepest sympathies to the families involved,” police said in a statement.
The incident occurred about 5 miles from Lake Hallie, a village in western Wisconsin with about 6,700 residents, and about 11 miles northeast of Eau Claire.