A 6-year-old boy who had been wading and playing in water with his father and several other people at a Rollinsford, New Hampshire, boat launch before he disappeared in the Salmon Falls River died Saturday evening.

The boy was pronounced dead at 7:22 p.m. after being air-lifted to Massachusetts General Hospital, Rollinsford Fire Chief Mark Rutherford confirmed Sunday night.

Rutherford said he had just been to a vigil for the boy, who was a Rollinsford resident and lived on Church Street, not far from the Bicentennial Park boat launch where the group was swimming. The park is located on the New Hampshire side of the river which separates Rollinsford from South Berwick.

“It’s kind of a swimming area,” Rutherford said. “With the beaches closed because of COVID-19, people are using alternate waterways. He was there with his father and in about 10 seconds he disappeared. It happens that quickly. People don’t realize. With kids that young, you have to watch like a hawk every second.”

Rollinsford police and fire responded to a report, made about 2 p.m. Saturday, that a boy had gone missing, according to a press release from the Rollinsford Police Department. Those two groups were supported by units from York Ambulance, South Berwick police and fire departments, along with the New Hampshire State Police, New Hampshire Fish & Game, New Hampshire Marine Patrol, and the Strafford County (N.H.) Sheriff’s Department.

The search, conducted on land, by boat and helicopter, continued until the boy who was pulled unresponsive from the Salmon Falls River at about 4:45 p.m.

Rutherford said that the boy was taken to Wentworth-Douglass Hospital in nearby Dover, New Hampshire, where he was worked on for over an hour before being airlifted to Massachusetts General. The boy was pronounced dead prior to being admitted.

Because the incident happened in New Hampshire waters, the ongoing investigation is being led by the New Hampshire Marine Patrol, a division of New Hampshire’s state police, according to both Rutherford and a spokesperson for the Rollinsford police. The identity of the boy is expected to be released by the New Hampshire Marine Patrol.

Based on Sunday’s posts to the Facebook page named “Rollinsford NH Happenings,” many residents of the small town were mourning the boy’s death by lighting candles or turning on an outside light, while others had left mementos and stuffed animals at the boat launch.