(LATimes) - A loan dispute over $1.2 million turned sour Monday when authorities said a Napa Valley vintner gunned down an investor among the grapevines in his vineyard, then later turned the gun on himself.

Robert Dahl, owner of Dahl Vineyards in Yountville, and business investor Emad Rasmy Tawfilis, 48, of Los Gatos were found shot to death after a spiraling series of events, according to the Napa County Sheriff’s Office.

“This is not how this was supposed to go,” Dahl’s attorney Kousha Berokim said. “This should have never happened.” 

Dahl and Tawfilis planned to meet Monday to “work out” planned payments as part of a resolution over the longstanding loan dispute, Dahl's attorney said. Tawfilis was seeking the balance of the loan debt as part of civil lawsuit.

Berokim said there was no reason to believe the meeting would turn violent. After all, he said his client and Tawfilis were “business professionals, calm, calculated and smart.”

The men met without their attorneys at Dahl’s vineyard, but “something tragically went wrong,” according the sheriff’s officials.

Witnesses told authorities an assault occurred inside the winery building, then Tawfilis ran away through the vineyard.

Dahl got into an SUV and chased Tawfilis, who called 911 and told a dispatcher he was shot. He said Dahl was chasing him in his truck and was trying to kill him.

Authorities said Dahl was repeatedly firing at Tawfilis with a .22 semiautomatic handgun.

When Tawfilis finally fell to the ground, Dahl walked up to him and executed him as deputies arrived at the scene, sheriff’s officials said.

Dahl hopped back into his SUV and fled on northbound State Route 29, prompting a police pursuit.

Joined by the Napa police and California Highway Patrol, sheriff's deputies followed Dahl until he finally crashed through a gate on private property. He finally came to a stop in a heavily wooded area.