Sen. Byrd Hospitalized

ABC's Z. Byron Wolf reports: On the same day the second longest sitting senator had brain surgery, the longest sitting senator was hospitalized with a fever.

Ninety-year-old Sen. Robert Byrd, D-W.Va., was hospitalized tonight after staffers noticed he was lethargic at work and a caregiver discovered he had a high temperature.

He is remaining overnight on the advice of his doctor, according to his spokesman, Jesse Jacobs, who said he was unsure which hospital his boss was at.

It is unclear at this point if the hospitalization is anything more than precautionary.

Byrd, who has had a spate of health problems recently -- he fell and also had a bad reaction to antibiotics, both of which led to hospital stays earlier this year.

And he has been seen on the Senate floor giving speeches from a wheelchair of late.