Authorities in Texas are investigating a deadly string of shootings that left three people dead across the Houston area on Wednesday, ending when the suspected gunman took his own life.

Police believe the same man was responsible for all three shootings, based on witness descriptions and the silver Ford Escape he was driving. His name has not yet been released.

The violence began shortly before 1 p.m. in Sugar Land, southwest of downtown Houston. Officers found a woman shot multiple times in the driver’s seat of a white SUV that had veered off the road, according to the Sugar Land Police Department. She was later pronounced dead at a hospital.

What was first thought to be a road rage incident was later determined to involve the shooter and victim, who had previously been in a relationship, police said. Investigators are still determining a possible motive and connection to the subsequent shootings.

About 30 minutes later, roughly six miles away, the gunman fatally shot a mechanic at an auto shop after what Houston Police Lt. Larry Crowson described as an altercation.

“We just know that the guy involved in the shooting there in Sugar Land drove to this location, went to the mechanic shop,” Crowson said.

As the suspect left the scene, he opened fire on a bystander recording video near a nearby warehouse, killing him, Crowson added.

When officers arrived in response to the second shooting, they found the suspect dead from a self-inflicted gunshot wound inside his vehicle.

Police continue to investigate what triggered the attacks.