Police have identified the good Samaritan who died early Wednesday when he and a friend stopped to help a stranded motorist on I-20 in DeKalb County.

Kleeon Cadogan, 29, was killed and his friend, Devon Witter, was critically injured after they were struck by a hit-and-run driver, according to Dekalb County police.

Witter remains in critical condition at Grady Memorial Hospital, according to DeKalb police.

The two men were changing a tire alongside the interstate near Panola Road about 4:30 a.m. when they were struck by a pickup truck.

According to police, Jodi DaCosta of Stone Mountain got a flat tire on her 1995 Nissan Maxima and called two friends to come change her tire.

While they were changing the left rear tire on the car, “a truck failed to maintain its lane and struck both of them,” according to DeKalb police Sgt. L. Westmoreland.

DeCosta was sitting in her car when the accident happened and was not injured.

Westmoreland said the driver of the pickup truck “continued on up the road, where we had a citizen follow the vehicle and actually got them to stop to where our units could catch up with the vehicle.”

The alleged hit-and-run driver, 29-year-old Andrew James Spencer of East Point, was arrested and booked into the DeKalb County Jail, charged with felony homicide by vehicle, felony hit-and-run and a felony lane violation.

Lee Hardeman was the motorist who chased down the alleged hit-and-run driver, who police said was driving a 2009 Dodge Ram 1500 pickup truck.

“This Dodge truck drifted from the center lane over to the first lane, and from the first lane and ran over the people and kept going,” he told The Atlanta Journal-Constitution.

“It kind of freaked me out,” Hardeman said. “I got on the phone and called 911 and followed the guy.”

At first, Hardeman said, he “kind of got nervous because I’d just seen somebody get hit” and gave the 911 operator the wrong direction that he was traveling on I-20.

Hardeman said he stayed behind the Dodge pickup.

“I was blowing my horn and I had my flashers on, and I let him know that I was right there on him,” he said. “I got real close to his bumper, and he kind of hit [the gas], so I hit it too, and he decided he would pull over.”

After pulling onto the shoulder of the highway, Spencer, the alleged hit-and-run driver, got out of his truck, Hardeman said.

“And I got out behind him, then he walked beside his truck and I asked him why he didn’t stop back there after he ran over them folks and he just looked at me,” he said. “I think he was going to keep going, but he found out I was following him and he decided to go ahead and just pull over.”

Hardeman, who installs sprinkler systems, said he was on his way from his Conyers home to a work site in Suwanee, and was behind Spencer for a while before the accident.

“He stayed in the same lane and drove nice, up until where the people were at,” he said. “Just right there, he drifted from the second lane to the first lane and ran over them people.”

The incident was the second fatal overnight pedestrian accident on a metro Atlanta interstate.

A man was struck and killed while trying to walk across the Downtown Connector at Williams Street about 10 p.m. Tuesday, Atlanta police said.

—Staff writer Michelle Shaw contributed to this report.