US Secretary of State Hillary Clinton will be spending at least 48 hours in the hospital after a follow-up examination to her concussion that she suffered early this month revealed the presence of a blood clot.
She is expected to remain at New York Presbyterian Hospital for the next 48 hours so doctors can monitor her condition and treat her with anti-coagulants, according to her spokesman Philippe Reines, the deputy assistant secretary of state.
"Her doctors will continue to assess her condition, including other issues associated with her concussion," Reines said. "They will determine if any further action is required."
Reines did not specify where the clot was discovered. Clinton, 65, was suffering from a stomach virus earlier this month when she fainted due to dehydration, causing the concussion.
Clinton, who plans to step down after four years as America's top diplomat if and when Senator John Kerry - President Barack Obama's choice to replace her - is confirmed by the Senate, spent the Christmas holidays with her family last week after working from home.
She was scheduled to return to work at the State Department this week. Her illness forced her to bow out of testifying Dec 20 before the House Foreign Affairs Committee on the deadly attack on a US diplomatic mission in Benghazi, Libya.
Deputies Thomas Nides and Bill Burns appeared in her place as she offered to appear before the Congress in January to give her testimony on the contentious subject that became a major election issue and forced US ambassador to the UN, Susan Rice, to withdraw herself from consideration as Clinton's successor.
In her busy tenure as secretary of state, during which she has logged more than 400 travel days and nearly a million miles on trips around the world that took her a couple of times to India too.