Authorities searching for a 7-year-old girl who disappeared with her father found the SUV police say he used kidnap her.

Clark Rockefeller is accused of grabbing the girl Sunday during a visit supervised by a social worker and fleeing in an SUV driven by someone else. Boston police confirm the car was found Tuesday and the operator was being questioned.

The divorced father, who has a murky background, and his daughter Reigh Boss were last seen Sunday night at Grand Central Terminal in New York.

Reigh lives with her mother in London. The visit Sunday was the first with her father in several months. Police say the 48-year-old Rockefeller has used many aliases.

A search was under way in New York. Police believe Rockefeller may try to flee the country in a recently purchased 72-foot yacht.

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Massachusetts posted an Amber Alert for Reigh, but canceled it Monday after New York City police reported that Rockefeller had been seen the night before at the city's Grand Central Terminal.

Authorities said they believe he may be trying to flee with his daughter Reigh on the yacht, possibly to Bermuda. The New York Police Department Harbor Patrol, the Coast Guard and the FBI searched for the yacht Monday around New York City and Long Island.

Boston police issued an arrest warrant for Rockefeller on charges of custodial kidnapping. He also was charged with assault and battery and assault and battery with a dangerous weapon because the social worker was injured while trying to hold onto the vehicle.

Reigh lives with her mother, Sandra Boss, who works in London as a partner in global management consulting firm McKinsey & Co. and who also is on the board of The Mount, Edith Wharton's estate at Lenox, Mass.

Little has been made public about Rockefeller's background.

Fraser Seitel, a spokesman for the descendants of John D. Rockefeller Sr., said Clark Rockefeller was not descended from that side of the wealthy family, and added there is no indication the fugitive was descended from William Rockefeller, John D. Rockefeller Sr.'s only sibling.

The Valley News, of Lebanon, N.H., reported in 2004 that Clark Rockefeller donated $110,000 to the town of Cornish, N.H., where he and Boss were part-time residents.

Rockefeller is a former director of Boston's exclusive Algonquin Club but resigned from the club three months ago, club manager Lassaad Riahi said Monday.

"What I do know is he's a gentleman. He's a kind man. Polite. Very, very intelligent," Riahi said. "I am very shocked."

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