BREAKING NEWS UPDATE: Teresa Heinz Kerry's condition was upgraded Monday from critical to fair.
(BOSTON) -- Teresa Heinz Kerry is in critical but stable condition at a Boston hospital after being transferred there from a hospital in Nantucket, where she and her husband, Secretary of State John Kerry, were vacationing.
A family spokesman said that Heinz Kerry was transferred to Massachusetts General Hospital from Nantucket Cottage Hospital, where she was taken by ambulance earlier on Sunday.
"Late Sunday afternoon, Mrs. Teresa Heinz Kerry was taken by ambulance to Nantucket Cottage Hospital, accompanied by her husband, Secretary of State John Kerry," Kerry's personal spokesman, Glen Johnson, said. "Once doctors had stabilized her condition, she was transferred to Massachusetts General Hospital in Boston, again accompanied by the Secretary."
Nantucket Cottage Hospital spokesman Noah Brown said Heinz Kerry, 74, was admitted on Sunday, but would not say why.
Sources close to the family told ABC News that she was taken from her home to the hospital by ambulance after falling ill Sunday afternoon, but they did not provide any details of her illness.
Heinz Kerry, the widow of former Sen. John Heinz, survived breast cancer after being diagnosed with the illness in 2009.
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