Officers discovered a 4-year-old girl, a 7-year-old boy and a 3-month-old girl near the water’s edge on the beach, known for its boardwalk and giant Ferris wheel.
At around 1:30 a.m. EDT (0530 GMT), police responded to a call to a Brooklyn apartment from a concerned family member who said a parent may have harmed their three young children, the police chief said. Kenneth Corey.
At the building, police met the father of one of the children, who expressed similar concerns, Mr Corey told a Coney Island press conference.
“He said he believed the wife and children were on the boardwalk here,” Corey said.
Officers searching the area found the children’s mother, 30, barefoot and wet. She was accompanied by other family members, but not children, Mr Corey said.
“The search has now intensified… aviation units, port units and additional shoreline surveys,” he said.
At around 4.45am (0845 GMT), officers found the children unconscious on the beach and rushed them to hospital where they were pronounced dead. The mother was then taken to a police station where she was questioned by detectives, Mr Corey said.
“So far she hasn’t said anything,” he said.