Chilling video captures the moment a gunman opened fire in broad daylight, fatally shooting a 17-year-old boy — who was officially identified by police early Wednesday.

The clip shows the assailant stepping out of a deli on Saratoga Avenue in Brownsville on Wednesday, pulling his weapon from his waistband and firing a shot that cops say hit victim Graig Bassett in the chest, killing him.

The attacker then is seen in the video — which was released by the NYPD — running off down the street after the 5 p.m. attack.

Bassett – who lived about a block from the scene – was taken to Interfaith Medical Center, where he was later pronounced deceased, cops said.

The motive for the shooting remained unclear Thursday morning, as the gunman remained on the loose.

Police describe the suspect as a male in late teens or 20’s, with a dark complexion, medium build, black hair and brown eyes.

He was last observed wearing black sneakers with a Nike logo on the side, black pants, a black jacket, black hooded sweatshirt and a black face mask.

The shooting came a day after after an eruption of gang-related violence in Upper Manhattan left three people — including two teen students — with gunshot wounds.