Lake Lanier turned deadly over the weekend, with a Buford teenager drowning after a boating accident and a Cumming man slipping underwater and never resurfacing.

The first tragedy occurred Saturday night, when a boating accident took place near the Dawson County line in North Hall.

Two boats with a combined 15 passengers collided, injuring two people and causing the death of Trevor Jones, 14.

Kaitlyn Smith, 13, of Social Circle, was flown by helicopter to Children's Healthcare of Atlanta at Egleston. Jack Struve, 57, of Cumming, suffered a jaw injury and was taken to North Fulton Hospital in Roswell.

All three victims were on the same boat, said Melissa Cummings, spokeswoman for the Georgia Department of Natural Resources.

Several agencies, including Hall County Fire Services, launched an immediate search for Trevor Saturday night. Rescue efforts were called off after dark.

They resumed the search early Sunday. As part of the efforts, authorities used the Georgia Department of Natural Resources' side scan sonar unit, a specialized system for detecting objects on the bottom of a body of water.

Hall County authorities found Trevor's body at 1:10 p.m. Sunday during what had been a search of waters off Toto Creek Park, Cummings said.

The park is near Ga. 136/Price Road at the Hall-Dawson County line.

Other agencies involved in the search included the Hall County Sheriff's Office dive team, Dawson County Fire Department's K-9 unit, Dawson County Sheriff's Office, Forsyth County authorities and the U.S. Army Corps of Engineers.

Also, chaplains from the DNR and the Dawson sheriff's office were on the scene, Cummings said.

No other details, including what caused the boat wreck, were available.

The accident is still under investigation.

Farther south on Lake Lanier Sunday morning, William G. Doster Jr. was wade fishing south of Browns Bridge in Hall County when he slipped underwater and didn't resurface, Cummings said.

He had been waist deep in Flat Creek when the incident occurred.

Authorities received an emergency call at 8:37 a.m. The family pulled him out at 8:45 a.m.

Doster had been in about 6 to 8 feet of water, Cummings said.

Along with the DNR, the Hall County Sheriff's Office and Hall County Fire Services responded to the scene.

Cummings said officials don't know why he suddenly slipped under the water.

So far this year, Lake Lanier has had nine drownings and six deaths resulting from boating incidents, she said.