A wild new video shows an unhinged man creep up and bash a stranger in the back of the head with a bottle in broad daylight while the victim is minding his own business walking on a Harlem street, police said.

The violent encounter unfolded around 1:30 p.m. on Aug. 23 as the unsuspecting man was walking with a pair of bags along Convent Avenue near W. 129th Street. That’s when the attacker ran up and hit him in the back of the head with a bottle, cops said.

The 66-year-old man fell to the ground and the brute continued to bash him with the bottle, cops said.

The victim refused medical attention after the assault.

Police released a video of the attack late Sunday in hopes someone in the public can help track the random attacker down.