Brian Dillon said he didn't have time to think about what to do when he saw a gunman shoot a man four times in the head outside the Empire State Building on Friday morning.
"I just reacted," the 44-year-old construction foreman told Newsday.
Dillon was working on a loading dock outside the Empire State Building when the first shot rang out. He said when he left the loading dock to investigate he saw a well-dressed man shooting bullets into a man already splayed on the sidewalk. He watched as the gunman, later identified as Jeffrey Johnson, walked away from the scene.
Dillon flagged down the cops and started screaming to them, "Get the guy in the gray suit! He just murdered somebody!"
A few moments later, police opened fire on the busy sidewalk, killing the gunman and wounding nine bystanders.
City officials have praised Dillon's actions. Mayor Michael Bloomberg called him a hero.
"He saw something, he said something," said Bloomberg.
Dillon, who lives in Westchester County, has been working at the site near the famous skyscraper since January. He said his colleagues yelled at him to stop when he headed in the gunman's direction.
Dillon said that when the police closed in on Johnson and the shooter raised his gun, the foreman was scared.
"I didn't want to die," he said. "I wanted to go home."
However, Dillon still believes he did the right thing.
"There are some things in life you just got to do, you know?" he said.
Celebrate Oscars 2017 with the top Irish movies of all time (VIDEOS)