22-year-old man arrested after allegedly shooting, killing pregnant girlfriend

MIDWEST CITY, Okla. (KFOR) — Police say 19-year-old Promise Cooper was shot and killed on Tuesday while riding in a car with her boyfriend.

44 minutes before being pronounced dead at SSM Health St. Anthony Hospital in Midwest City, Cooper had called 911.

On the call, she told a dispatcher, "He's telling me he was gonna harm me and my family. He's riding around with a ski mask on."

After making the call, Cooper got in the car with her boyfriend, 22-year-old Tristan Stoner.

An affidavit details the two going to a dispensary, leaving, and then approaching the intersection of Reno and Sooner.

The document stated that Cooper was hot, and rolled the the passenger side window down.

Stoner told police that a Dodge Charger next to them also rolled down their window and looked suspicious.

Police say Stoner pulled a gun and shot at the vehicle, one of the shots struck Cooper in the chest.

Once he saw that she was injured, he took her to the hospital where she later died.

Angela Beatty, the Vice President of Programs and Engagement at Young Women's Christian Association spoke with News 4.

"One of the leading causes of injury in pregnant women is domestic violence. Unfortunately, oftentimes as abuse doesn't start until there's some sort of permanency in the relationship," said Beatty.

Midwest City Police says Stoner changed his story several times, but after searching his phone they found messages that he sent to Cooper, upset about the pregnancy and wanting her to get an abortion.

He also threatened Cooper over text.

Stoner is facing charges of Second Degree Murder.