A Keene woman was found dead Sunday at a gathering site for a counterculture group in Utah, according to the authorities.

The death of Susan Wilkinson, 39, is not believed to be suspicious, but remains under investigation, said Lt. Brian Gardner of the Wasatch County Sheriff’s Office in Heber City, Utah.

Another attendee of the 43rd annual Rainbow Gathering reported Wilkinson’s death at about 9 a.m. Sunday, Gardner said. She was found lying outdoors at the campsite, he said.

Gardner did not know if Wilkinson had attended the gathering with friends or family. Officials have contacted Wilkinson’s family about her death, he said.

An autopsy of Wilkinson was conducted this week, and now the sheriff’s department is awaiting results of toxicology tests, which could take three months, Gardner said.

The Rainbow Family was formed in Oregon in 1970 with the goal of promoting peace and nonviolence. It holds large gatherings at national forests annually. The group does not have any formal affiliation, according to its website.

This year’s gathering is expected to draw up to 20,000 people to the area of the west fork of the Duchesne River in the Uinta-Wasatch-Cache National Forest, where attendees will stay until August.

Alyssa Dandrea can be reached at 352-1234, extension 1435, or adandrea@keenesentinel.com. Follow her on Twitter @ADandreaKS.