A New York man is being hailed as a hero after he dove into freezing cold water to rescue a 2 year-old puppy.

The incident occurred last week, when Harper the dog was out for a walk in Brooklyn with her petsitter. Suddenly, the petsitter was hit by a taxi that had run a stop sign, and while the petsitter was only minimally injured, Harper still ran off in a panic.

At that same moment, Gabe Castellanos was celebrating his birthday with friends on the Brooklyn Barge when he noticed Harper struggling to stay afloat in the water. Gabe and his pals thought the dog had gone for a swim to escape the heat, but when the pet sitter yelled to them to let them know what had happened, they knew they had to do something.

Thinking fast, Gabe stripped down to his underwear, grabbed a life jacket, and jumped into the water. As pedestrians cheered him on and a police helicopter flew overhead, Gabe managed to catch up to Harper as she frantically swim.

Harper was so panicked that she bit Gabe on the hand and face, chipping his tooth in the process. Undeterred, Gabe continued to help her and guided her back to shore so that she could be reunited with her pet sitter.

Though he had to get a fake tooth because of the incident, Gabe said afterwards that he understood Harper’s panic and that he did not hold it against her.

“I was like, ‘Aw it’s alright, I needed teeth work anyway,’” he said.

Harper’s owner said that she was so grateful to Gabe for saving her dog that she wants to throw him another birthday party as a thank you. Find out more about this in the video below!