Ramsey County prosecutors have charged at 21-year-old St. Paul man with murder for allegedly gunning down another man as he sat in a car with the suspect's former girlfriend.

The Ramsey County Medical Examiner said Toumai Gaynor was the man found in the driver's seat of a vehicle with critical gunshot injuries last Thursday. Fire department medics rushed Gaynor to Region's Hospital that morning but he died hours later, marking the 10th homicide in St. Paul this year.

St. Paul police officers arrested Martavious Deavionne Roby-English, 21, on Monday for Gaynor's death. The Ramsey County Attorney's Office charged Roby-English with second-degree murder and second-degree attempted murder, alleging that he tried to kill a woman seated in the car with Gaynor during the shooting.

Roby-English's first court appearance is Wednesday. According to charging documents:

Officers responded to reports of a shooting in St. Paul's North End neighborhood at around 2:28 a.m. on May 30. They found Gaynor inside a Toyota Camry which had backed into a yard on the 800 block of Simcoe Street. Blood covered Gaynor. Bullet holes riddled the vehicle's windshield. Wounds to Gaynor's hip, arm and head shallowed his breathing and left him unconscious.

Region's Hospital staff later determined the 21-year-old was brain dead, and declared him deceased at around 11:16 that day.

Police interviewed a woman, referred to as "GK" in charging documents, who was in the car with Gaynor during the shooting. GK said she and Gaynor, her friend, were in her Camry to drop Gaynor off somewhere for the night. The two spoke for around an hour in the car as GK said she was arguing with Roby-English via text messages.

GK and Roby-English had a relationship for three years, she told investigators, which began six months before Roby-English was sentenced to prison. The woman planned to visit Roby-English after dropping Gaynor off but changed those plans as Roby-English grew angry at her delayed text responses.

Investigators believe Roby-English approached as that conversation ended and Gaynor tried to turn the car around. GK said a man in a white hoodie stood in front of the car and began shooting. She ducked and told Gaynor to drive but said he didn't move. Gaynor recognized Roby-English when she says he pulled her out of the Camry. She said Roby-English claimed it was self-defense because Gaynor fired first.

She told police that she ran back to the scene and called 911 to help Gaynor. She also claimed to throw Gaynor's gun behind the car because she worried he would get in trouble for it if he lived. She said the gun was hot to touch, suggesting it had been fired.

Surveillance footage captured Roby-English hiding behind a van and looking at his phone minutes before the shooting. That footage shows Roby-English running down the street where Gaynor was turning the Camry around before a male voice is heard yelling, "Get out of the car or I'll kill you! Get out!"

The footage then captured the sound of seven gunshots.

Authorities arrested Roby-English in his home on Monday. He told investigators that he sent $250 to GK days before the shooting which she had not returned. He claimed to grow angry at GK when she seemed to ignore his messages and when she turned off her phone's location settings. He says he approached GK as she was in the vehicle with Gaynor that night and told her to get out of the car. He heard gunshots then, telling investigators that he fired at the Camry.

Roby-English said he checked on GK and Gaynor but fled fearing that he would be shot. When GK asked why he fired, Roby-English said he responded, "I'm sorry, but it was an accident and he shot first."

Prosecutors say Roby-English's criminal history includes two violent crime convictions: Roby-English earned an adult sentencing on June 16, 2022, for a second-degree assault charge after he shot into a vehicle, hitting a man in the chest. Roby-English was also sentenced for second-degree assault on May 4, 2022, after gunfire struck an innocent bystander as Roby-English and others launched a gang-related shootout in a store parking lot.