A 7-year-old boy is fighting for his life after being pulled from Wirth Like in Minneapolis' Theodore Wirth Park in midafternoon Friday.

The boy's grandmother alerted lifeguards that he was missing about 2 p.m. Lifeguards quickly cleared the lake of swimmers to search for the boy, who was pulled from 4 to 6 feet of water in a swimming area, according to Hennepin County Sheriff's Office spokeswoman Lisa Kiava.

Kiava said she didn't know how long he had been underwater.

The child, identified Saturday as Keylen Rashan Thorton, was unconscious when taken to North Memorial Medical Center in Robbinsdale. He was later transferred to Children's Hospital and Clinics in Minneapolis, where his condition was not available Saturday.

Officials have issued several cautions to swimmers this summer in the wake of a spate of drownings and near-drownings last year, warning that drownings typically happen quietly and quickly. And they can occur with even the briefest lapse in supervision of children.

Two minutes under water can cause a child to lose consciousness. After four to six minutes, irreversible brain damage sets in, according to the Minnesota Department of Health.

Officials urge people to wear life jackets when on lakes, streams or rivers; to advocate for supervision by lifeguards at pools and beaches; to take swimming lessons, and for adults to not mix alcohol and boating or swimming.

Last year, 40 people drowned in non-boating incidents in Minnesota, including a 6-year-old boy who drowned in Wirth Lake last July.

Several people have drowned this year in Minnesota. In the most recent, 26-year-old Joel Berge of Fargo, N.D., died Thursday night while swimming in a water-filled pit in Clay County in western Minnesota.

On June 10, 3-year-old Linden Halverson drowned in Lake Edna near Nisswa.

A spate of drownings

Six days later, Dylan Dusabek of Isanti drowned in Long Lake in Isanti County after falling from a boat. His body was recovered in 8 feet of water. He wasn't wearing a life jacket.

In late May, a 4-year-old Arizona boy was rescued but 64-year-old Peter Johnson drowned in Crow Wing County when the canoe they were in capsized in the Gull River north of Baxter. Both were wearing life jackets.

In late June, Stephen Fritze, 50, of Watertown, S.D., drowned after his kayak hit debris and overturned in the Minnesota River in Nicollet County. He wasn't wearing a life jacket, and officials say he may have gotten caught on branches underwater.