01/20/2009 at 03:45 PM EST
Massachusetts Sen. Edward Kennedy was removed from a post-swearing-in ceremony luncheon in National Statuary Hall Tuesday due to what is being called a medical emergency.
Kennedy, who is waging a battle against malignant brain cancer
, suffered a seizure, but is resting comfortably, according to Dr. Edward Aulisi, chairman of neurosurgery at Washington Hospital Center, where Kennedy is hospitalized.
"Senator Edward Kennedy experienced a seizure today while attending a luncheon for President Barack Obama in the U.S. Capitol," Dr. Aulisi said Tuesday afternoon. "After testing, we believe the incident was brought on by simple fatigue. Senator Kennedy is awake, talking with family and friends, and feeling well. He will remain at the Washington Hospital Center overnight for observation, and will be released in the morning."
Kennedy's family had been optimistic about the status of his health, according to reports, and the 76-year-old has been recovering from June brain surgery on the tumor.
Still, in August, the sole surviving brother of President John F. Kennedy lent his voice in strong support of the nomination of Democratic candidate Barack Obama – and the "Lion of the Senate" has vowed to remain an active voice in health-care reform under President Obama.
Robert Byrd was separately taken out of the Congressional luncheon. One of the oldest members of Congress, Byrd, 90, received the aide of medical personnel after having trouble eating, according to reports.
Later in the afternoon, Byrd's office said the senator was "okay."
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