US Secretary of State John Kerry's wife, philanthropist and heiress Teresa Heinz Kerry, has been hospitalised with an unspecified medical condition.
Glen Johnson, a State Department official who serves as Mr Kerry's personal spokesman, announced her illness but did not give details.
Mrs Heinz Kerry, 74, was in critical but stable condition, a Boston newspaper reported.
"Late Sunday afternoon, Mrs Teresa Heinz Kerry was taken by ambulance to Nantucket Cottage Hospital, accompanied by her husband," Mr Johnson said in a brief written statement released by the State Department.
"Once doctors had stabilised her condition, she was transferred to Massachusetts General Hospital in Boston, again accompanied by the secretary," he added.
Massachusetts General Hospital is among the top US medical centres and is one of the Harvard Medical School's teaching hospitals.
Earlier, a source close to the family said Mrs Heinz Kerry's trip to the hospital from the family's summer residence in Nantucket was necessitated by a "medical condition" rather than an accident.
The source, who spoke on condition of anonymity, said Mrs Heinz Kerry was flown to Boston on her own plane.
Mrs Heinz Kerry was born in Mozambique and is the widow of Pennsylvania Senator John Heinz III, an heir to the Heinz food fortune.
Mr Heinz, a Republican, died in a helicopter crash in 1991.
Mr Kerry is one of the richest US senators, mostly due to Mrs Heinz Kerry's fortune.
She is known for being outspoken and famously told a reporter to "shove it" during her husband's unsuccessful presidential bid in 2004.
