JERUSALEM — A comatose Ariel Sharon underwent four hours of emergency surgery Saturday afternoon to remove part of his badly damaged intestines, an aide and hospital officials said.

The Israeli prime minister's condition was good after part of his intestines was removed, the aide said. Hadassah Hospital said he was returned to the intensive care unit. Before the surgery, doctors said Sharon's life was in danger.

The aide spoke on condition of anonymity because he was not authorized to discuss Sharon's medical condition.

The prime minister underwent his seventh operation in five weeks after an abdominal scan revealed severe damage to his digestive tract.

Hospital officials said before the surgery that Sharon's life was in danger. It was not clear whether surgeons were able to stabilize him.

Sharon has been in a coma at Hadassah Hospital for five weeks, attached to breathing and feeding tubes, since suffering a devastating stroke Jan. 4.

The premier's condition deteriorated early Saturday. An abdominal scan revealed that blood was not reaching parts of his intestines and that his digestive tract had suffered severe damage, Hadassah spokeswoman Yael Bossem-Levy said.

The restricted flow raised the possibility of necrosis, or death of cells or tissue, in the intestines, she said. Necrosis has many possible causes, including restricted blood flow to tissue.

"Sharon's life is in danger," Bossem-Levy said before the surgery.