7-year-old girl swims to shore after her boat capsizes in 'extremely dangerous' Illinois lake, killing her grandfather and great-grandfather

A seven-year-old girl was able to swim to safety after a tragic boating accident on an Illinois lake in which her grandfather and great-grandfather were killed.

The two men, identified as Clarence B. Royster, 80, of Gary, Indiana, and Clarence B. Royster III, 53, of Merrillville, Indiana, were pronounced dead after their bodies were recovered Sunday from the LaSalle Lake State Fish & Wildlife Area in Marseilles, the LaSalle County coroner said.

Shortly after 12 noon, police received a call about a boater in distress. They found a capsized 5.2-meter Crestliner boat on the 813-hectare lake. According to a state conservation agency, this can create “extremely dangerous conditions.”

Neither man was wearing a life jacket, police said. The girl, who was wearing a life jacket, was able to swim to shore and received assistance from visitors who helped her contact her mother and grandmother.

The men's bodies were found around 7:45 p.m.

A seven-year-old girl swam to safety after a tragic boating accident in an Illinois lake that killed her grandfather and great-grandfather

The lake is located about 84 miles southwest of Chicago and is known among locals for its waves and dangerous conditions, the Illinois Department of Natural Resources warned

The investigation into the cause of the accident is ongoing.

The man-made lake is located about 84 miles southwest of Chicago and is surrounded by levees, according to the Illinois Department of Natural Resources.

This design “can create extremely dangerous conditions for careless boaters,” the department said in a guide.

“The surface of the lake can change very quickly and the waves can be excessive,” adds the guide.