ATLANTA (AP) — Gov. Brian Kemp declared a state of emergency Thursday, giving him the option of calling in the Georgia National Guard in response to a violent protest in downtown Atlanta over the killing by authorities of an environmental activist said to have shot a state trooper.

The declaration allows the Republican governor to call up to 1,000 Guard members over the next 15 days to help “subdue riot and unlawful assembly.” A Kemp spokesperson said later that there has been no mobilization so far and the order is a precautionary measure that gives the governor the ability to act if necessary.

Protesters set a police cruiser on fire Saturday night and threw rocks and lit fireworks in front of a skyscraper that houses the Atlanta Police Foundation. Officials have said no citizens or responding officers were injured, but the windows of three businesses were damaged.

In his State of the State address on Wednesday, Kemp decried the protesters as “out-of-state rioters” who “tried to bring violence to the streets of our capital city.” He said it was “just the latest example of why here in Georgia, we’ll always back the blue.”

Lawmakers also voiced outrage and disapproval, although some Democrats tempered their remarks with calls to look for solutions to violence as well.

Authorities arrested six people Saturday night on charges including domestic terrorism and said unspecified “explosives” were recovered. The violent protesters were a subsection of hundreds of demonstrators who marched to mourn the death of the protester, who went by the name Tortuguita.

Tortuguita, whose given name was Manuel Esteban Paez Terán, was killed Jan. 18 as authorities were clearing a small group of protesters from the site of a planned Atlanta-area public safety training center that activists have dubbed “Cop City.”

The Georgia Bureau of Investigation has said Tortuguita was killed by officers after shooting and seriously wounding a state trooper in the abdomen. The bureau says the bullet came from a handgun that Tortuguita purchased legally in 2020.

Activists have questioned officials’ version of the incident, calling it a “murder” and demanding an independent investigation.

Opponents of the training center have been protesting for over a year by camping out at the site and building platforms in surrounding trees.

They say the $90 million project involves cutting down so many trees that it would be environmentally damaging. They also oppose spending so much money on a facility they say will be used to practice “urban warfare.”

Police officials say the state-of-the-art campus would replace substandard offerings and boost police morale beset by hiring and retention struggles in the wake of violent protests against racial injustice after George Floyd’s death in 2020.

Kemp called out the National Guard to guard the state Capitol, the governor’s mansion and other public facilities during the Black Lives Matter protests in 2020 and kept them mobilized and providing security at the Capitol well into 2021.

They provided a very visible and heavily armed presence on some days, including after Jan. 6, 2021, when groups had threatened to send armed protesters to every state capitol.

Racial justice demonstrators accused troopers and other state law enforcement officers of unjustifiably using tear gas on at least two different occasions in 2020.

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