A York woman is missing after she and her two friends overturned their canoe at Flagstaff Lake, according to Maine game wardens.

Wardens have been searching for the woman since Saturday night in and around Flagstaff Lake in Dead River Township, which is north of Carrabassett Valley.

Two men, a woman and her friends were “canoeing to their campsite on Flagstaff Lake when their canoe overturned” at about 5:20 p.m. Saturday, the Maine Warden Service said in a statement.

“After the canoe flipped, the occupants, who were not wearing life jackets, grabbed their life jackets and began to swim to shore. The two men and the dog made it to shore, and started looking across the lake, but could not see or find the woman. The two men who were already hypothermic started hiking out a road to find help. After an hour’s walk, they were able to get help and call 911” on Saturday evening, the warden service said.

Game wardens began searching at about 10 p.m. Saturday. The name of the missing woman is being withheld until family members can be notified of the search.