Hollywood star Dwayne Johnson has penned an emotional note for his friend and "Jumanji: Welcome to the Jungle" co-actor Kevin Hart, who suffered major back injury after a car crash.

Johnson on Monday shared a still from their movie "Jumanji: Welcome to the Jungle" on Instagram.

The actor, who is popularly known as "The Rock", captioned the image: "Stop messing with my emotions brother Kevin Hart. We have a lot more laughing to do together. Love you man. Stay strong."

Hart suffered severe back injuries and was hospitalised following a major car crash in California.

The accident happened just before 1 a.m. on Sunday on the winding and treacherous Mulholland Highway. Crash scene video, shows Hart's car deep in a gully about 10 feet off the road, reports tmz.com.

The vehicle smashed through wooden fencing along the roadside, and its roof was completely crushed.