Israeli Prime Minister Ariel Sharon was still undergoing surgery and his fate would be known in a few hours, Shlomo Mor-Yosef, director of Hadassah Hospital, told reporters on Thursday.
It had been seven hours since Sharon was transferred to the hospital. The prime minister suffered from high blood pressure, a significant stroke, and a massive internal bleeding within his brain, Mor-Yosef said.
Sharon was gravely ill and his condition was very critical at this moment, he added.
After the first phase of the surgery, Sharon was again rushed to the operation theater, and the next phase would last for at least another several hours, Mor-Yosef said.
Sharon, 77, was transferred to the hospital Wednesday night.
Before dawn Thursday, Sharon's aide Ra'anan Gissin said the prime minister's condition was stable and the surgery was "proceeding as expected."
He said the cabinet was functioning despite Sharon's illness.
"A state isn't run only by the people who stand at its head ... All the ministers and all the ministries are functioning," he added.
Sharon's power had been transferred to Vice Prime Minister Ehud Olmert, Cabinet Secretary Yisrael Maimon said.
Sharon's personal physician said he expected the leader "to emerge from (surgery) safely."
Meanwhile, Channel 10 quoted hospital sources as saying while the bleeding in Sharon's brain was extensive, it was not in the brain stem.
However, senior political sources feared that Sharon might not recover from the cerebral hemorrhage.
The prime minister had originally been scheduled to undergo a heart procedure Thursday morning.
On Dec. 18, 2005, Sharon was taken to Hadassah Hospital following a mild stroke. Doctors said he would not suffer long-term effects from the stroke, but they discovered a birth defect in his heart that apparently contributed to the stroke.
Since the stroke, Sharon had been receiving blood thinners to try to prevent a recurrence of the clotting that caused the stroke, according to hospital sources.