An off-duty Kentucky state trooper spotted a knife-wielding man apparently assaulting his ex-girlfriend on the side of an interstate, but the quick-thinking trooper raced to save her life, police announced Tuesday.

"I said, if you hadn't have pulled up here, you know I would have been dead," the woman, Glory Purvis, told WLEX.

Hazard Trooper Jeffrey McWhorter was driving home from training in Frankfort on Monday afternoon. Investigators say he stopped when he noticed 40-year-old Travis Phillips pulling his ex-girlfriend from their SUV, eventually getting on top of the woman and choking her.

"He told me that if he couldn't have me, nobody could," Purvis added.

Police say the suspect pulled out a knife when the trooper approached him on the shoulder of I-64.

McWhorter pulled out a Taser, ordering the man to drop the knife and get on the ground, police add. They said after the man refused, the trooper deployed his Taser, freeing the woman.

Medical teams rushed to treat the woman, and said she was not too badly hurt.

Police say Phillips now faces charges including assault and terroristic threats. He was recovering in the hospital Tuesday after he cut himself with his knife, investigators add.