Authorities were warned that the shooter was planning an attack on the Yellowstone facility

YELLOWSTONE NATIONAL PARK – Hours before a gunman opened fire at the entrance to a Yellowstone National Park employee dining room, wounding a ranger, authorities had been warned he was planning a mass shooting at the facility, officials said Thursday.

This revelation came after authorities released videos and other new details about the July 4 shooting in which rangers posted to protect the Canyon Village facility killed 28-year-old Samson Lucas Bariah Fussner of Milton, Florida, after opening fire with a semi-automatic rifle.

Authorities had been searching for Fussner for hours before the shooting after a security guard called 911 shortly after midnight on July 4 and said Fussner had just taken a woman hostage and told her he was going to attack the staff dining room.

Videos from park rangers' body-worn cameras show a chaotic scene during and immediately after the shooting in the world's first national park, a place millions of people enjoy each year for its wild nature and tranquility. In one video, a ranger can be seen shooting Fussner from a vehicle door inside the building.

In another video, another ranger outside the building approaches the wounded Fussner, who is lying motionless on the ground, dressed in black and with one hand raised up at the elbow. Fussner remains motionless while the ranger takes his semi-automatic rifle and unclips it from its strap.

According to park officials, Fussner was also armed with a semi-automatic pistol.

Body camera footage shows a third ranger running from nearby staff dormitories toward the scene, shouting to the unseen people, “Go back to your dormitories!” As the ranger runs, a dozen gunshots are heard.

“Stay down! Stay down!” the ranger shouts to two people crouched behind the front wheel of an SUV. Authorities have blurred the faces of all the people in the videos to protect their identities.

As the ranger approaches the corner of a building, two other rangers stand there with guns pointed at him and someone shouts: “The suspect is on the ground, he’s not moving!”

At the rear entrance where the gunman struck, photos showed at least 18 bullet holes in the walls. That's where the first ranger to fire with Fussner was wounded in a “lower extremity,” according to park officials.

The footage shows rangers approaching their wounded colleague, who is sitting on the concrete landing of a staircase.

“Is everything okay?” someone asks.

“Yes, I'm fine,” the ranger replies, giving a thumbs up.

According to the park administration, paramedics tried to help Fussner, but a doctor pronounced him dead.

Aside from Fussner, the ranger was the only person physically injured that day, in an area crowded with about 200 park employees and visitors. The ranger was treated at a hospital and released after a few days, park officials said.

Park officials have not determined the identities of the rangers involved in the altercation, including the five at the scene. Four of the five activated their body-worn video cameras during and shortly after the exchange of gunfire.

Under National Park Service policy, rangers are required to activate their cameras whenever they make contact with a person, “except in an emergency situation that requires immediate action to protect life or safety,” according to a National Park Service report on the sequence of bodycam videos, a recording of the first 911 call, and photos and diagrams of the crime scene edited Thursday.

The shooting prompted authorities to close Canyon Lodge, a complex of hotel rooms, cabins and dining facilities, for several days. The facilities are operated by Yellowstone's largest tourism concessionaire, Xanterra Parks and Resorts, where Fussner had worked through the summer season.

Park rangers had been searching for Fussner for hours before the shooting. Late on the evening of July 3, Fussner held another concessionaire against her will in her Canyon Village apartment with a gun and a knife.

Early on July 4, the woman said Fussner threatened to kill her and others, including threatening to commit a massacre at Independence Day events outside the park, park officials said in a statement five days after the shooting.

On Thursday, the text and voiceover added that Fussner told the woman he planned to carry out mass shootings in the employee dining room as well as at Fourth of July events outside the park. Officials have not said whether Fussner released the woman or if she fled.

Yellowstone officials did not immediately respond to an email Thursday asking why they did not disclose earlier that Fussner had told the woman he was planning a mass shooting in the dining room.

The incident is still being investigated by the FBI and authorities have not yet accused the rangers of any wrongdoing in the confrontation. Not all materials related to the confrontation have been released.

The FBI did not immediately answer Thursday whether anyone other than the park rangers witnessed the shooting.

After receiving a 911 call shortly after midnight on July 4 that Fussner had taken the woman hostage, rangers found Fussner's vehicle but not him. Inside they found a handgun.

More than 20 police officers, including a special operations team from the park, were involved in the subsequent nighttime search for Fussner. The next morning at around 8 a.m., Fussner approached the service entrance to the cafeteria and opened fire.

Fussner's Facebook page said he was proud to have landed a concessions job in Yellowstone, a typically seasonal job that often requires him to cook and serve food to the park's 3 million summer visitors. Such jobs are usually given to slightly younger people in their early 20s, often college students visiting from other countries.

Fussner posted a photo of his Xanterra Parks and Resorts badge and photos of himself in snowy Yellowstone landscapes in mid-May. The posts did not suggest anger or any other motive.

Yellowstone often makes headlines for sometimes fatal accidents involving wildlife and the park's famous hot springs, but shootings are rare, despite the park's millions of visitors and the region's high rate of gun ownership.