An eyewitness said the baby was only wearing diapers.
Her husband Monte called emergency services before reaching into the water to retrieve the boy.
Officials want to know: How long was the boy in the water before an Oklahoma family spotted him Sunday afternoon?
"My dad hopped in, pulled the baby out and started to do CPR on it".
Tourists from Oklahoma discovered the child lying unconscious and unresponsive near the Manhattan side of the Brooklyn Bridge at around 4 p.m., according to police.
"There was no pulse, no respiration", Campbell, a chiropractor, said.
No parent or guardian was present at the scene, police said. The Medical Examiner is working to determine the baby's cause of death.
The baby's parents were not on scene. It was about 11 months old, 11 to. "So I handed the phone to her and got the baby".
"Someone knows that child", she told the Times.
The Associated Press says Monte Campbell's wife, Diana, first noticed the child.
Campbell and the officers tried to revive the baby using CPR until an ambulance arrived and rushed him to NewYork-Presbyterian Hospital/Lower Manhattan, where he was pronounced dead, police said.
The baby boy, thought to be about 8 months old, was transported to a local hospital where he was pronounced dead. "It's just unreal, you don't come to the city expecting to see things like this, to see babies floating in the water".