A child died of a gunshot wound on Saturday at a popular campground in Yellowstone National Park, according to park officials, who said the girl's mother reported that her young daughter had shot herself with a handgun.
Emergency responders were unable to resuscitate the girl after her mother called emergency dispatchers from a campsite near Yellowstone Lake, park spokesman Al Nash said in a statement.
The names of the mother and girl in the incident, which is under investigation, were not released pending notification of extended family members, Nash said. The child's age was also not released.
A U.S. law that took effect in 2010 allowed people to carry guns into national parks as long as federal, state and local firearms laws were met, according to the National Park Service.
Although hunting is permitted at a handful of national parks, including Grand Teton in Wyoming, hunting or even firing a gun is unlawful in Yellowstone, according to park literature.
The forested campsite where the shooting occurred sits near a developed area in the Wyoming section of the park known as Grant Village, which features a ranger station, lodge, stores and other amenities.
Yellowstone, which was the first area designated a U.S. national park and is among the country's most popular outdoor destinations, spans 2.2 million acres of pine forests, river valleys, mountain lakes and geysers in parts of Wyoming, Montana and Idaho, and attracts about 3 million visitors a year.