Golf pro killed in Georgia had witnessed a crime, police say

July 6 (UPI) -- A professional golfer who was one of three people fatally shot on a Georgia golf course was killed because he witnessed a crime, police said Tuesday.

The gunman suspected of killing Gene Siller was also connected to the deaths of two other people on the golf course Saturday, police said, adding that the suspect was at large.

"It does not appear [Siller] was targeted," but he was killed because he "happened upon a crime in progress involving the unknown suspect and the two deceased males," the Cobb County Police Department said in a statement to CNN Tuesday.

As director of golf at Pinetree Country Club in Kennesaw, about 27 miles north of Atlanta, Siller went to check on a report of an unauthorized pickup truck around 2:30 p.m. He was found with a gunshot wound to the head shortly after on the green of the 10th hole, police spokeswoman Shenise Barner told The Atlanta Journal-Constitution.

Authorities said Siller was pronounced dead at the scene.

Paul Piersen, the vehicle's owner, was found dead along with another man in the bed of the truck, police said. The third slain man's name has not been released.

The investigation is ongoing, a suspect has not yet been named and motive is not yet known, police told CNN and the AJC.

Siller, 41, is survived by his wife and two sons. A GoFundMe page to help the family with funeral and memorial expenses has surpassed its $500,000 goal.

"Tragedy has stricken the Georgia Section PGA in the loss of our member, Gene Siller," the Georgia PGA tweeted Saturday. "Thoughts and prayers for his family and the Pinetree Country Club family."