Four Amish children were dead and one was missing on Thursday after the horse-drawn buggy they were riding in with their mother overturned on a bridge in northeastern Kentucky, the authorities said.

The family were members of the Amish community in Peasticks, in Bath County, about 50 miles northeast of Lexington, Michael Gray, the deputy coroner, said in an interview on Thursday.

They were returning home from church on Wednesday afternoon when their buggy flipped while they were trying to cross a low-water bridge spanning a branch of a waterway that feeds into the Licking River, he said.

Their mother summoned help. “She was washed away, too, but then she got to the side and she climbed out of the creek,” Mr. Gray said.