UPDATE 9-US Sen. Kennedy hospitalized after seizure

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By Svea Herbst-Bayliss

BOSTON, May 17 (Reuters) - U.S. Sen. Edward Kennedy, a leading Democrat and patriarch of a prominent American political dynasty, suffered a seizure on Saturday but hours later was talking with family at his side in a Boston hospital.

Kennedy, 76, was rushed from the family vacation compound at Hyannisport, Massachusetts, to Cape Cod Hospital at 9 a.m. (1300 GMT), before being airlifted to Boston.

"He is undergoing a battery of tests at Massachusetts General Hospital to determine the cause of the seizure," his office in Washington said in a statement.

A Kennedy aide said later that by Saturday afternoon the senator was joking with family members.

Senate Democratic Leader Harry Reid, after talking with Kennedy's wife, Vicki, told reporters in Reno, Nevada, that the senator "will be fine," a Reid aide said.

Reid said the senator had a seizure, but "woke up fighting," the aide added.

The Boston Globe reported Kennedy, youngest brother of assassinated U.S. President John F. Kennedy, suffered one seizure at his Cape Cod home and a second seizure aboard the helicopter transport flight to Boston.