WASHINGTON, DC (AP) -- Doctors at Washington Hospital Center are assessing Sen. Edward Kennedy after he fell ill at an inauguration luncheon for President Barack Obama.

The hospital says Kennedy is awake and answering questions. He's been battling a brain tumor.

Sen. Orrin Hatch was at the event and says "It looked like a seizure." He says he was with Kennedy when the senator was put into an ambulance, and that Kennedy was conscious and gave him a grin.

Former Vice President Walter Mondale says Kennedy was swapping stories with others at their table when "something happened" and "he just stopped."

But Sen. Chris Dodd says Kennedy was talking when he was put into the ambulance, adding "the good news is he's gonna be fine."

A fellow senator, Democrat Jay Rockefeller of West Virginia, says President Barack Obama went over to check on Kennedy after he became ill.

Kennedy had attended Obama's oath-taking on the Capitol's west Front.

During a talk to members of Congress and others, Obama called attention to Kennedy, saying "I know that while I was out of the room, concerned was expressed about Teddy."

Obama said that Kennedy "was there when the voting rights act passed, along with John Lewis, was a warrior for justice."

"And so I would be lying to you if I did not say that right now a part of me is with him," Obama added. "And I think that's true for all of us. This is a joyous time. But it's also a sobering time. And my prayers are with him and his family and (Kennedy's wife) Vicki."

There are conflicting reports about whether another veteran Senate Democrat, Robert Byrd, also suffered medical problems at the luncheon.

Sen. Byrd's office says the 91-year West Virginian decided to leave an inauguration luncheon after Sen. Kennedy was stricken, but not because of any medical problem of his own.

Spokesman Mark Ferrell said that Byrd was sitting at the Capitol luncheon with Sen. Kennedy when the Massachusetts senator took sick.

Ferrell said, "Sen. Byrd did not have a medical issue - he is just fine."

Ferrell added: "Sen. Byrd made the decision to leave the luncheon once Sen. Kennedy was being taken from the room by medical personnel. Sen. Byrd is currently in his own office in the Senate Hart Building and is doing fine, though remains very concerned about his close friend Ted Kennedy."

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