Authorities said investigators are probing the slaying of a millionaire businessman whose weighted body was pulled from an upstate New York lake with three bullets in the head.

The victim, George Perry, 64, a former General Motors executive, who disappeared from the Grand Hyatt Hotel in Manhattan in January, was found at the bottom of Lake Tiorati in Harriman State Park, about 50 miles northwest of here, on April 8 and was identified three days later, Orange County, N.Y., District Attorney Joseph Brown said.

Brown confirmed that as many as a dozen state police investigators are working on the mysterious slaying. "It certainly appears to be a professional killing," he said.

Brown would not say where Perry, shot three times in the head with a .22 gun, was slain. But investigators said he was dead when his body was dumped in the lake in the 46,000-acre park that straddles Rockland and Orange counties. Weights had been tied to the body, and Brown said the site was near a road with easy access to the water.

Perry, born in Czechoslovakia of American parents and fluent in several languages, spent most of his adult life traveling the world for GM, and had been debriefed routinely by the CIA after some of his trips, sources said.