A loud "pop" startled the father and son as they demolished a trailer at a South Side mobile-home park late Monday afternoon.

When the two men turned their heads, they said, they saw a man in an SUV fire a second shot out the driver's side window. A man standing on a lawn was struck by a second bullet to his chest.

"He sat there and watched the guy as he fell to the ground," 24-year-old John Marteney Jr. said of the shooter, whom Columbus police identified as 74-year-old Ronald Payne. The victim was identified as David E. Sellers, II, who was 30.

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The SUV driver said nothing before or after he fired the shots, Marteney said. He said the man then drove slowly out of Fairlane Mobile Home Park, which is off the intersection of South High Street and Williams Road.

Marteney said he immediately called 911 and ran after the SUV, relaying information to the dispatcher.

Payne called 911 shortly after the shooting and told a dispatcher that he shot Sellers and was thinking about hurting himself, police said in a news release early Tuesday.

Columbus police cornered Payne in his SUV behind the Kroger store in the 3600 block of South High Street, about a quarter-mile from the shooting scene. Police were unable to get Payne to surrender, and he died by suicide in the vehicle. Paramedics pronounced him dead at the scene at 4:50 p.m.

Back at the mobile home park, in the 100 block of Niles Drive, responding Columbus police officers performed chest compressions on Sellers. Sellers' wife also performed CPR, Marteney said.

"I yelled, 'Come on, you can do it! Keep breathing, you can do it.'"

But Sellers was pronounced dead by paramedics at 5:01 p.m. on the lawn he had been mowing just before he was shot.

"I was thinking, 'This is crazy.' I got nieces and nephews out here. They could have got shot. Me and my father are out here in the line of fire," Marteney said. "It is very shocking to me."

John Marteney Sr., 59, said he, too, was struck by how the shooter "just sat there and watched to make sure he died. It was a cold-blooded murder, that's what it was."

A neighbor, who asked that his name not be used, said that Payne and Sellers were formerly friends. Payne suffered from post traumatic stress disorder and had become aggravated with Sellers, supposedly over Sellers' use of a motorbike, the neighbor said.

Investigators believe the shooting stemmed from a long-term dispute between the two men, the release said.

The release does not detail the nature of the dispute.

Sellers' death was the city's 30th homicide of 2019.

jwoods@dispatch.com

@Woodsnight