There were no signs of forced entry, and the apartment, located on the Upper West Side of Manhattan, was in good order. His dog, a German shepherd, was found shut in the bedroom. Levin's body lay in the kitchen, with a pool of blood around the head. The coroner's office said a single bullet pierced his skull and brain. The time of death was not disclosed.
Neighbors told the Associated Press that Levin was a humble man who never mentioned his family's wealth. "I had no idea he had such famous parents," said the cashier at a nearby deli where he stopped every day. She said he had dated several women recently.
Gerald Levin, 58, has been chairman of Time Warner for four years. Last year, he engineered the purchase of Turner Broadcasting System, bringing CNN into the same company as Time magazine and HBO. Jonathan was the oldest of Levin's five children.
(Updated 6 p.m. PT)