R&B Singer Keke Wyatt Allegedly Threatened to Shoot Woman Before Assault Arrest

R&B sensation Keke Wyatt allegedly threatened to put a bullet in another woman's head ... allegedly extending a gun out of her car window while shouting out warnings ... this according to her arrest warrant.

We've obtained the affidavit from the warrant that lays out law enforcement's version of events leading up to Keke's arrest earlier this week ... with an officer claiming they were dispatched to an area in Georgia on September 20 regarding an alleged domestic disturbance.

According to the docs, the incident apparently went down between two people during a custody exchange ... with cops saying Keke was also there, but wasn't one of the two people involved in the exchange.

Cops say a witness told them they saw a fight break out between the two people ... before Keke allegedly pulled out a black 9mm Beretta and pointed it through the window of the car.

The witness told cops they saw Keke extend the gun out of the car window and shout, "Let that bitch come over here, so I can blow her brains out."

Cops say Keke admitted to holding the gun ... but denied pointing it out the window or making any threats.

As we reported ... she was arrested and booked on charges of terroristic threats, simple assault, and cruelty to children. The report says three children were nearby when the alleged incident occurred, hence the cruelty to children charge.