The Associated Press is reporting that Secretary of State Hillary Clinton has been admitted to the hospital with a blood clot following a concussion, according to a spokesperson.

CBS News correspondent Margaret Brennan tweets that a spokesperson for Clinton confirmed that the former First Lady has been taken to New York Presbyterian, and that the hospital will monitor her for the next 48 hours.

According to Foreign Policy's Josh Rogin, Clinton was scheduled to return to work this week following a three-week recovery from a stomach virus and concussion.

The illness was first reported December 10, when Clinton's office announced that it was the reason the Secretary of State had canceled a scheduled trip to the Middle East. On December 15, Clinton's doctors reported that she had also sustained a concussion after fainting from her illness.

Conservative pundits and bloggers have accused Clinton of faking the illness in order to avoid testifying in an open Congressional hearing about the Sept. 11 attacks on the U.S. Consulate in Benghazi, Libya. Clinton has said she will testify in front of both House and Senate committees when she returns to work.