Kentucky shooting: Manhunt continues for highway gunman who shot five as police rule out ‘road rage’ motive

Police found an AR-15 discarded in thick brush near the site of the shooting. They believe the weapon was used in the attack

Police are still searching for the gunman in a mass shooting that injured five people and turned a Kentucky interstate into a “madhouse” on Saturday.

The shooting occurred on Interstate 75 around 5pm local time, according to the Laurel County Sheriff's Office. Investigators said they do not believe the shooting was the result of a road rage incident, and have identified Joseph Couch, 32, as a person of interest in the shooting.

When Laurel County Sheriff's deputies arrived at the scene near London — a small city approximately 75 miles south of Lexington — they found that nine vehicles had been damaged by bullets near Exit 49.

"When our first two units got to the scene there, they said it was a madhouse: people on the sides of the road, emergency flashers going, bullet holes, windows shot out, nine vehicles shot. Can you imagine that? Just chaotic," Deputy Gilbert Acciardo said on Sunday during a press conference.

All five people who were shot are in stable condition, though one suffered "very serious" injuries, according to CBS News.

A picture released by the Laurel County Sheriff’s Office on their Facebook page of Joseph A Couch, a person of interest in the shooting (Laurel County Sheriff's Office/A)

Police continued their search on Sunday. Investigators found an AR-15 discarded in a thick, wooded area near the interstate. They believe it was the weapon used in the attack, according to Acciardo.

"We're going to go in and we're going to find this guy," Acciardo said.

Multiple agencies joined the deputies during the search on Sunday, including the US Marshal Service, the FBI, and the Bureau of Alcohol, Tobacco, Firearms and Explosives. Drones and infrared technology are also being used to scan the area for any sign of Couch.

Traffic stopped on Interstate 75 during the shooting near London, Kentucky (AFP)

The deputy said he did not believe the shooter was in a vehicle, and said it was "definitely not road rage."

Deputies have not determined a motive yet.

As the manhunt is ongoing, residents living near the scene of the attack have been urged to stay inside and to watch for anyone matching Couch's description. Police described him as caucasian, 5'10, and weighing approximately 154 pounds.

Police said he should be considered "armed and dangerous" and said anyone who thinks they've seen him should report the sighting to police.

The Laurel County Sheriff's Office warned residents not to approach anyone they believe to be Couch.

London Mayor Randall Weddle advised residents on Facebook to stay inside and not to try to take the law into their own hands, in part to protect investigators searching for the shooter.

“If you think you hear something outside of your home, please do not go outside shooting,” Weddle said. “Our officers could be in that area or first responders. Call 911.”