A teenager cliff diving south of the Twin Cities at a lake that routinely draws trespassers was killed when another jumper landed on him in the water, authorities said Tuesday.

The body of 17-year-old Garrett N. Berg, of Farmington, was located in Lake Byllesby west of Cannon Falls about 8:15 p.m. Monday by members of the Goodhue County dive team, the Sheriff’s Office said.

Berg, a Farmington High School student and wrestler, jumped off the cliffs at the lake about 5:25 p.m. and was soon hit by a second juvenile who also dove in, according to the Sheriff’s Office.

The Southeast Minnesota Medical Examiner’s Office is conducting an autopsy to determine the cause and manner of Berg’s death.

Deputies went to the area around the cliffs earlier Monday and sent away 30 people, the Sheriff’s Office said.

The cliffs “can only be accessed by crossing private property,” a message that is posted in the area, according to the Sheriff’s Office, which added that it “routinely responds to remove and/or cite violators.”