The off-duty officer who fatally shot Delrawn Small after they stopped at a red light in Brooklyn over the summer was indicted on Monday for second-degree murder and first-degree manslaughter, according to a source.

The officer, Wayne Isaacs, was expected to be arraigned in Brooklyn on Tuesday morning, the source said.

Isaacs had been stripped of his gun and badge and placed on modified duty about a week after he shot and killed Small. Isaacs had just finished his shift at the 79th Precinct when he and Small, 37, both stopped for the light just after midnight on July 4.

The shooting was first reported as road rage and police said that Small apparently punched Isaacs several times before the cop pulled his gun.

But a video released afterward appeared to show Small walking up to the cop’s car and immediately being shot, stumbling back and then collapsing.

The state attorney general’s office took over the investigation into the shooting in July. An executive order signed by the governor gave the AG the power to take over any investigation where an officer kills an unarmed civilian.

This is the sixth case the AG’s office has taken over under the executive order, and the second such case in the city. Schneiderman also took over the investigation into the death of Richard Gonzalez, who died in March after being handcuffed after police responded to a call that Gonzalez had taken drugs and become aggressive.