"I thought they were firecrackers at first," Sweetland said of the gunshots. He is an emergency room physician and was at the rally when the chaos played out.
He lives in Pennsylvania but practiced for years in Angels Camp, the Sierra Conservation Center in Jamestown, and Merced.
"I remember Merced very fondly," he told Action News. People were very friendly."
As shots rang out Saturday and the Secret Service rushed the stage, Sweetland says he heard a woman calling for help in the crowd.
"He's been shot. He's down. I knew she was talking about somebody down there," Sweetland said he heard.
He ran to the man's aid.
"All I could think of was a voice in my head telling me, 'Go, go. They need your help. Get over there,'" Sweetland said.
A photo captured of Sweetland shows the raw emotion on his face and the blood on his shirt after he performed CPR on the bystander for two minutes.
The victim was there with his family.
"I'll never forget the look on their faces of horror. Being totally appalled," Sweetland said.
Pennsylvania Governor Josh Shapiro identified the victim Sunday, saying Corey Comperatore died a hero. He was a girl dad, a husband, a retired firefighter.
"Corey dove on his family to protect them last night at this rally," Governor Shapiro said. "Corey was the very best of us."
"He did what, instinctively, a lot of fathers would do in that situation, and he acted quite bravely," Sweetland said.
He is still shaken by the attempt on Trump's life that killed Comperatore and injured two others.
Sweetland is now calling for unity and urging his fellow Americans to tone down the political rhetoric.
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