Narconon Arrowhead is located on the shores of Lake Eufaula near Canadian, northeast of McAlester. The facility can house up to 200 patients, known in the program as students.

Narconon Arrowhead is the flagship branch of an international drug-rehabilitation organization rooted in the teachings of Church of Scientology founder L. Ron Hubbard. The program’s unorthodox treatment includes five-hour daily sauna sessions and large doses of niacin — vitamin B3. Additionally, patients go through training based on Hubbard’s teachings.

A multiagency investigation of Narconon Arrowhead began after Stacy Dawn Murphy, 20, died from a drug overdose at the facility in July 2012. Her death followed the deaths of patients Gabriel Graves in 2011 and Hillary Holten in 2012.

Attorney David Riggs, representing Narconon Arrowhead, has said he is aware of the grand jury investigation and that “we provided the information that they wanted.”

Among witnesses called by the grand jury is Eric Tenorio, a supervisor at Narconon Arrowhead and other locations for 12 years. Tenorio said the centers operate as a recruiting tool for the Church of Scientology. He said he eventually left his job and began filing complaints about Narconon, including that employees falsely claimed to be certified drug counselors.