Three young children are dead, and their mother was found soaking wet and barefoot, wandering the Coney Island boardwalk early Monday morning, police officials said.

A family member called 911 at 1:40 a.m., warning police they feared the mother might have harmed her three young children, aged 7, 4, and just 3 months old, according to NYPD Chief of Department Kenneth Corey at a press conference on the Coney Island boardwalk Monday morning.

The call touched off a neighborhood-wide search of the family’s apartment on Neptune Avenue, local hospitals, and the Coney Island boardwalk. Officers ran into the father of one of the children, who expressed similar concerns about the family and directed officers to the boardwalk.

About 90 minutes later, after receiving another 911 call, police tracked down the 30-year-old mother wandering the boardwalk, barefoot, wet, and non-communicative, Corey said. She was with other family members at the time but not the children, police said.

The search for the children intensified with aviation and harbor units, and people on foot searching the shoreline, Corey said.

At 4:42 a.m. officers found the three children unresponsive at the water’s edge, about two miles from where they had found the children’s mother. They administered CPR and rushed them to Coney Island Hospital, where all three were later pronounced dead. Their names were not released immediately.

The Medical Examiner’s office, which is tasked with determining how the children died, had not yet determined their cause of death.

The children’s mother was in custody and police were trying to question her, but she had not been charged, Corey said. A preliminary investigation indicated “no prior history of abuse or neglect,” of the children, he added.

“We are looking for witnesses, we don't know exactly what happened here,” Corey said. “We’re trying to piece this all together.”

Anyone with information about the incident is asked to call Crime Stoppers at 800-577-TIPS.

This is a developing story.