Authorities said a driver took off with a police officer inside a car Thursday, reaching speeds up to 71 mph on a busy road.

Police say the smell of marijuana initiated a pat-down after the officer pulled over the driver for a traffic violation.

Marietta police said the traffic stop took place just after 7:30 a.m. when the officer pulled the car over for a traffic violation. He smelled marijuana and asked the driver to step out, police said.

Police said the driver cooperated at first but took off when police backup arrived.

Investigators said the officer was pulled into the car after putting the driver in a headlock. A second officer at the scene was shoved to the ground, and the driver took off and accelerated, police said.

Police said the car stopped about a mile away from the site of the traffic stop.

Earlier reports said the officer was dragged by the car, but dashcam video showed the officer was completely in the vehicle even though the door was open. At some point, the officer closed the door in order to keep from falling out, police said later.

The driver and two passengers tried to run away, police said, but they were taken down by other responding officers and arrested.

"Certainly, it was a chaotic scene,” said Marietta Police Officer Chuck McPhilamy. “We're incredibly happy and fortunate that the officer pushed back into traffic wasn't run over or hurt, even happier the officer that became trapped partially into the vehicle was able to stay just out of harm's way enough that he wasn't pushed out of the vehicle or pulled in any further or hurt. Now that we know there were handguns involved, certainly there could've been a gunfight inside the car.”

Lauren Foreman, The Atlanta Journal-Constitution, contributed to this report.