Travis County investigators say they don't know much about a man found dead in Lake Travis Sunday, but an ID they found on his body at least let them identify him.

Boaters found the body floating in shallow water near a boat ramp around Mansfield Dam just after 9:00 Sunday morning.

Chief John Chapman of the Travis County Park Rangers said they can't release the man's identity until they contact any family members.  Investigators checked into any missing person reports that might list the man, but say they found nothing.

Deputies do not believe this case to be a homicide at this time.

As officials blocked off the area around the boat ramp, fishermen like John Herzog were still in the water.

"I was actually fishing when EMS pulled up," said Herzog. "Then the EMS command unit pulled up and then that's when I start to realize it's not just a walk in the park kind of accident."

Herzog and others were detained on the water while investigators looked around.

"I've fished here tons of times," Herzog said. "I mean this is not something you'd expect at all."

Investigators will now wait for autopsy results to determine what exactly caused the man's death.