ATLANTA (AP) — Authorities said they killed a man who shot and injured a Georgia state trooper Wednesday morning as law enforcement officers tried to clear protesters from the site of a planned public safety training center just outside Atlanta.

Officers from several law enforcement agencies were conducting an operation to clear people out of the area around 9 a.m. when someone fired at them and officers shot back in self-defense, Georgia Bureau of Investigation Director Mike Register said during a news conference. A trooper was shot in the abdomen and the man who shot at the officers was killed at the scene, Register said.

The trooper was rushed to a hospital, where he underwent surgery, Georgia State Patrol Col. Chris Wright told reporters. The trooper’s vital signs are good and he’s in stable condition, but he is in the intensive care unit and “he’s still not out of the woods yet,” Wright said.

Register and Wright declined to identify the trooper or the man who was killed, citing the active investigation and the need to notify family members.

Register said the “clearing operation” was being conducted in the same area where a handful of people were arrested last month and charged with domestic terrorism. DeKalb County District Attorney Sherry Boston said at the time that people attacked firefighters and police officers as state and local law enforcement officers with rocks and weapons as the officers removed barricades blocking some entrances to the site.

The GBI and other law enforcement agencies “embrace a citizen’s right to protest, but law enforcement can’t stand by while serious criminal acts are being committed that jeopardize the safety of the citizens we’re sworn to protect,” Register said.

People are “illegally occupying” the area and are committing criminal acts that endanger the community, including arson, beating people up, using explosives and setting booby traps that have the potential to seriously hurt someone, he said.

Register said four people had been detained with possible charges to come and that the situation remains fluid.

Georgia Gov. Brian Kemp released a statement earlier this month applauding the arrests and saying “they will not be the last we will take down as this project moves forward.”

“Domestic terrorism will NOT be tolerated in our state, and we will not hesitate, we will not rest, we will not waver in ending their activities and prosecuting them to the fullest extent of the law,” he said in the statement posted on Twitter.

Opponents of the training center have been protesting for over a year by building platforms in surrounding trees and camping out at the site. They say that the $90 million project, which would be built by the Atlanta Police Foundation, involves cutting down so many trees that it would be environmentally damaging. They also oppose investing so much money in what they call “Cop City,” which they say will be used to practice “urban warfare.”

The 85-acre (35-hectare) property is owned by the city of Atlanta but is located just outside the city limits in unincorporated DeKalb County, and includes a former state prison farm.

In an email to news outlets Wednesday morning, opponents of the training facility said they gathered outside the DeKalb County courthouse on Monday, Martin Luther King Jr. Day, to demand that Boston drop the charges against people who were arrested at the site on Dec. 13 and 14. They “spoke about how the movement to stop cop city continues Atlanta’s history of resistance to state violence,” the email says.