He appears to be pinching closed a severed artery protruding from the victim’s thigh, stanching the flow of blood from a torn and shattered leg.

“I kept talking to him. I kept saying, ‘Stay with me, stay with me,'” Arredondo told the Portland, Maine, Press Herald.

Another frequently published photo shows him afterward, carrying an American flag soaked in blood.

Arredondo had been at the race to support a group running for fallen veterans, one of them his son, according to the Maine newspaper, which described him charging in to help the wounded after the explosions.

Afterward, he was shaking, sometimes violently, as he told bystanders what had happened.