(CNN) -- Authorities searched door to door after a powerful storm cut a swath through northern Wisconsin Sunday night.
At least 25 homes suffered severe damage, said Mark Handlin with the Lincoln County Sheriff's Office, who said the worst damage was north of Merrill, located about 170 miles northwest of Milwaukee.
Crews are working to clear downed trees and power lines, Handlin said. A shelter has been set up at a local motel.
Two residents were airlifted to a larger regional hospital because of the extent of their injuries, said Brian Sladek, director of Lincoln County emergency management. Other minor injuries were reported.
CNN's Greg Morrison contributed to this report.