The Nebraska Game and Parks Commission is investigating a fatal boating accident on Branched Oak Lake. The Lancaster County Sheriff's Office said 32-year-old Eric Jarecki of La Vista, and his cousin, 25-year-old Jason Hofsaas of Omaha were killed in the accident.

Sheriff's deputies said the two men were driving a red, 1996 Vyper speed boat when they made a sharp turn and were thrown from the boat.

Authorities said the men struggled in the water as the boat circled them out of control. Eventually both men were struck by the propeller and the men drowned before rescue crews could save them.

"They were without floatation device or life jacket and were unable to swim to shore, or rescue themselves, so consequently they ended up drowning in the lake and had to be recovered by water rescue personnel," said Capt. Brad Thavenet with Lincoln Fire & Rescue.

No one else was injured and the authorities said the boat did not run into any other boats.

Witnesses called 911 shortly after the incident, according to the sheriff's department.

Several agencies responded to the scene, including Lincoln Fire and Rescue's water rescue team and Raymond Fire Department.

The Nebraska Game and Parks is handling the investigation. Stacey Lewton with that organization said there's no evidence the boat hit anything or that the boat flipped. He said they will try to determine the boats RPM level at the time of the accident to get a speed estimate. He also said they will determine if a mechanical malfunction caused the accident.

The Lancaster County Sheriff departments said speed is likely a factor and autopsies will be performed.

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