Two people were killed in a predawn head-on collision that shut down a major south Cobb County thoroughfare during the early part of Wednesday’s morning commute.

The crash happened around 3:30 a.m. on Austell Road north of Sweetwater Lane in Austell.

According to the preliminary investigation, an Austell police officer was attempting to make a traffic stop on a silver 2005 Acura TL on Pontiac Circle near Maxham Road, but the driver fled when the officer attempted to approach the vehicle, Cobb County police said.

The driver, 29-year-old Chrystina L. Stanford of Roswell, was speeding northbound on Maxham Road in the southbound lanes and collided head on with a gold 2000 Acura 3.5RL, Cobb police spokesman Officer Michael Bowman said in a news release.

The driver of the gold Acura was identified as Gary V. Sheppard, 41, of Marietta.

Both drivers were pronounced dead at the scene.

Billy Cooper, who lives nearby, described the crash as a “big loud bam, like a shotgun” that woke him up.

“It sounded like an explosion,” Cooper told The Atlanta Journal-Constitution. “It shook my house.”

One northbound lane had reopened by 6 a.m., but both southbound lanes remained blocked until 6:30 a.m., when all lanes were reopened in both directions.

Cobb County police are assisting the Austell Police Department with the investigation. No charges are expected to be filed, Bowman said.

—Angel K. Brooks contributed to this article.