Park rangers shot and killed a gunman who’d fired at them after making threats in Yellowstone National Park early Thursday morning.

The shooting happened after rangers received reports of a person with a gun making threats, the National Parks Service (NPS) said in a statement. When the officers arrived, the unnamed person shot at them and they fired back, according to the NPS. The shooter injured one officer before the rangers fatally shot him.

The officer who was shot is in stable condition at a local Wyoming hospital, the NPS said on Thursday afternoon.

The Federal Bureau of Investigation (FBI) is now investigating, the NPS said. The shooting happened in Yellowstone’s Canyon Village, a cluster of lodges for visitors, which is currently closed as officers look into the incident.

There is no longer any danger to visitors, the NPS said.

Earlier this year, Yellowstone rangers had to step in when a reportedly drunk tourist harassed a group of bison and kicked one of the animals in the leg.

Rangers arrested 40-year-old Clarence Yoder for attacking the animal. They said he “sustained minor injuries from the encounter with the bison.” He was charged with intoxication, disorderly conduct, and approaching and disturbing wildlife.

Rangers also arrested the man driving the car Yoder was found in. They charged the driver with driving under the influence, failing to yield to a police car and disturbing wildlife.

The men, who were both from Idaho, pleaded not guilty.