The incident took place in Ulster County.
The girl had been reported missing around 5:45 p.m., Monday, June 7 at Sojourner Truth Ulster Landing Park in the town of Ulster.
"Initial responding units immediately were directed to the water for a report of a 9-year-old female from Kingston who had been swimming with family members and had been swept under the water and had not surfaced," said Town of Ulster Police Chief Kyle S. Berardi.
Marine units, dive teams, and aviation continued to search for the girl into the night until the search was called off, due to darkness, the chief said.
On Tuesday, June 8, at 7 a.m., marine units, dive teams, and aviation with all available resources resumed the search.
At 9:42 a.m., marine units and divers located the victim in the general vicinity of where she was reported missing, Berardi said.
The name of the girl is not be released out of respect for the family, he added.
The Kingston School District said on its homepage that it "mourns the tragic loss" of one of its elementary school students.
The district is offering counseling to any student, parent, or staff member. For help, call 845-943-3826.
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