A courageous St. Lucie (FL) County deputy was stabbed in the neck during a "completely unprovoked attack" late Wednesday night, yet still managed to chase after the suspect, authorities said.

According to the St. Lucie County Sheriff's Office, deputies responded to a rollover crash around 11 p.m. and found a vehicle unoccupied, WPTV reports.

Deputy Cody Colangelo, 22, eventually located the driver of the car, identified as Leigha Michelle Day, 21, walking along the shoreline down an embankment near the crash scene.

"He (Colangelo) did such a phenomenal job. He was so nice and compassionate with her," Chief Deputy Brian Hester said at a news conference Thursday. "Hey, we're gonna help you. Come on, let's get you back up here. You don't have to be afraid."

Suddenly, without warning, Day turned and stabbed Colangelo in the neck with a knife, nicking his carotid artery, officials say.

Day ran off and Colangelo fired one shot at her, but missed.

Despite being stabbed and suffering a severe injury, Colangelo chased after Day while applying pressure to his wound, authorities said.

At that point, Colangelo lost sight of Day and began radioing other deputies for help. Authorities eventually found Day hiding down an embankment and took her into custody.

Colangelo underwent a two-hour surgery where doctors replaced part of the artery in his neck with one from his leg. Amazingly, the deputy is now in stable condition in the hospital and is expected to make a full recovery.