At least two people died Sunday in Virginia when a highway "road rage incident" reportedly spiraled into a violent mass stabbing, authorities said.
The attack occurred on I-495 southbound near Little River Turnpike in Annandale, Fairfax County, roughly 30 minutes from Washington, D.C.
One of four stabbing victims, as well as a dog, died from the incident, authorities said. The suspect was also killed when responding officers returned fire.
Officials said the attack does not appear to be terrorism-related.
"A Virginia State Police trooper was called to the scene at approximately 1:17 p.m. for a reported road rage incident," Virginia state police said.
"The stabbings occurred before or as the trooper was responding," authorities added in a statement to Fox News Digital.
Responding police reportedly found a male suspect armed with a knife. During the confrontation, the trooper reportedly shot the suspect in self-defense. Authorities added that the responding trooper was left unharmed.
State police identified the deceased victim as a 39-year-old woman who succumbed to her injuries. The dog involved was also fatally stabbed.
The incident prompted a shutdown of the highway amid reports of a heavy police presence.
"I-495 and 495 Express Lanes southbound past Gallows Road is closed due to a major incident," the Virginia Department of Transportation’s Northern Virginia office said, adding that the lanes were "blocked due to police activity."
The crash is under investigation.
The Fairfax County Police Department told Fox News Digital that it is assisting state police troopers.