An off-duty state trooper shot a man who came at him with a knife Saturday afternoon outside a southeast Atlanta gas station, authorities said.

According to the GBI, the Georgia state trooper was getting gas at the BP on Boulevard near I-20 when he saw one man chase another into the store and followed them.

“Witnesses report that one man was armed with a knife and was attempting to stab the other man,” GBI spokeswoman Nelly Miles said in a news release. “The trooper gave commands for the man to drop the knife.  The trooper left the store, and the man with the knife followed him.”

Authorities said the man advanced toward the off-duty trooper as he backed away and told him to drop the weapon, prompting the trooper to shoot the man.

The man, who has not been identified, was taken to Grady Memorial Hospital about 5:30 p.m. He remained in critical condition Saturday night. The trooper was not injured.

Saturday’s incident is the 11th police shooting the GBI has been asked to investigate this year. The Atlanta Journal-Constitution also tracks officer-involved shootings that don’t involve the GBI, and those numbers sometimes differ from the GBI’s tally.

A Georgia State Patrol spokesman said the Department of Public Safety will also conduct its own investigation into Saturday’s shooting.

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