The 22-year-old man suffered shortness of breath, and was flown to a hospital in Seattle for hyperbaric treatment
Lake McDonald
Lake McDonald
| Credit: George Rose/Getty

An 18-year-old woman was killed and a 22-year-old man injured following a scuba diving accident in a national park in Montana, authorities said.

The woman and man were part of a group of six people scuba diving in Lake McDonald at Glacier National Park on Sunday, the National Park Service said in a press release.

A park ranger responded to a report of an accident just before 6 p.m., and members of the group tried unsuccessfully to resuscitate her, as did first responders.

The woman, who was from Missoula, was declared dead, the release said.

The man, meanwhile, suffered shortness of breath, and was rushed to a local hospital before being flown to Seattle for hyperbaric treatment.

Hyperbaric treatment is a therapy involving pure oxygen in a pressurized environment, and is often used to treat decompression sickness, which is a potential risk of scuba diving, according to the Mayo Clinic.

RELATED VIDEO: Sister of Woman Found After 12 Days in Zion National Park Says Sibling Was on a 'Journey of Fasting'

The release said the group began their scuba diving outing near the dock of Lake McDonald Lodge about two hours prior to the accident. Bystanders drove to nearby Apgar Village when the incident occurred in order to obtain cell service to call 911.

The incident remains under investigation, and the victims’ names have not yet been released.

The National Park Service said Lake McDonald is a popular scuba diving spot, as it has submerged artifacts.

A permit is not required to dive in Glacier National Park, and diving equipment is not subject to inspections.