The 8-year-old had been in the water at least an hour. An update of his condition was not immediately available.
The incident was reported about 2:20 p.m. The boy was attending a family gathering.
He reportedly was swimming from a dock to a floating device about 40 feet away, Snohomish County sheriff's Lt. Rodney Rochon said.
Police were told that he attempted to climb onto the raft but was struggling. Some people on the raft saw him slip under the water, Rochon said. They initially believed he intended to swim under the raft and surface on the other side. The boy never came up.
Lake Roesiger firefighters and sheriff's divers raced to the scene. Boaters on the lake tried to locate the boy.
The sheriff's office launched its helicopter to aid in the search.
Once on scene, divers quickly found the boy about 27 feet down.
Paramedics immediately began life-saving efforts. The boy was taken to a local hospital.
No other details about the incident were available Sunday evening.
Sunday's incident was the second time over the weekend that a child was hospitalized after being rescued from water.
A 3-year-old girl was unconscious when she was pulled from a swimming pool Saturday at a home in Edmonds. She was breathing by the time paramedics took her to Harborview Medical Center in Seattle.
There was no word on her condition Sunday.
Diana Hefley: 425-339-3463; firstname.lastname@example.org.
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