A Conyers man trying to flee a traffic stop on an I-75 exit ramp had a good reason for attempting to run Wednesday night, according to investigators.

He had a half-kilo of heroin inside his vehicle, according to the Georgia State Patrol.

Troopers had stopped 36-year-old Alvaro Jimenez-Santana at the Delk Road overpass for a traffic violation, Sgt. Charles Chapeau said. Jimeniz-Santana initially stopped and had given a trooper his driver’s license, Chapeau said.

“During the course of the traffic stop, the driver decided to go jump back into his car,” Chapeau said.

Jimeniz-Santana then allegedly drove off, sending the trooper to the ground and knocking him unconscious. Jimeniz-Santana drove a short distance before getting out of the SUV and running, Chapeau said. The suspect was located during a manhunt involving numerous law enforcement agencies.

While searching for Jimeniz-Santana, investigators found a half-kilo of heroin he allegedly threw from his vehicle. Jimeniz-Santana was arrested near Franklin Road and charged with aggravated assault against a police officer and drug possession.

The veteran trooper, whose name was not released, was in stable condition at a local hospital, where he was being treated for a head injury, Chapeau said.

The incident and police investigation temporarily blocked lanes of Delk Road and parts of I-75 northbound late Wednesday.