The deaths of three children found unconscious on the Coney Island shoreline Monday were ruled homicides, the city's Office of the Chief Medical Examiner said Tuesday. The cause of death was drowning.

The three children's mother, identified by police as Erin Merdy, remains under psychiatric evaluation at a hospital and has not been charged, officials said.

A concerned family member called 911 around 1:40 a.m. on Monday saying they believed a woman may have harmed her children, police said.

Police then conducted a 90-minute search across the Brighton Beach boardwalk, the beach, nearby streets and the woman's apartment.

After an additional 911 call, officers were directed to Brighton 6th Street and the Riegelmann Boardwalk, where they found a 30-year-old woman — barefoot, soaking wet and despondent — believed to be the mother of the missing children, police said.

The three children, all of whom showed signs that they had drowned, were found shortly after on the shoreline near West 35th Street, the NYPD said.

The children — Oliver Bondarev, a 3-month-old boy, Lilana Merdy, a 4-year-old girl, and Zachary Merdy, a 7-year-old boy — were rushed to NYC Health + Hospitals/Coney Island, where they were pronounced dead, police said.