Palestinian leader Yasser Arafat remained critically ill at a military hospital near here late Thursday night after slipping into unconsciousness on a day dominated by rumors, confusion and false reports that he had died.

A French military spokesman at Percy hospital southwest of Paris said that the 75-year-old Arafat's condition had become "more complicated."

The spokesman, Christian Estripeau, reading a brief statement he said was authorized by Arafat's wife, Suha, confirmed that the Palestinian leader had been transferred Wednesday afternoon to a unit "suitable for his condition." He added, "Mr. Arafat has not died," but would not take questions or provide details.

A former adviser to Arafat, who asked not to be further identified, said the Palestinian leader was being supported by a respirator. "He is in very, very critical condition -- he's not breathing by himself," said the former adviser, speaking from Arafat's damaged headquarters in the West Bank city of Ramallah.

Cabinet Minister Saeb Erekat, the chief Palestinian negotiator with Israel and one of Arafat's longtime advisers, said he had spoken by phone to members of Arafat's entourage outside Paris. The word was that Arafat's situation was difficult and that he was not improving, Erekat said.

Earlier in the day, Erekat said he had talked to Suha Arafat, who had described her husband's condition as "stable but difficult." Erekat said she told him that reports Arafat was in a coma were "not true. She told me he is not in a coma."

Other Palestinian leaders, who gathered in an emergency session at Arafat's Ramallah compound, also denied reports in the Israeli news media that Arafat was brain-dead and on life support. "Arafat has no type of brain death," Arafat's personal physician, Ashraf Kurdi, told al-Arabiya television.

Still, given the lack of official word, rumors swirled for most of the day. President Bush was asked at a news conference about reports of Arafat's death, and replied: "My first reaction is God bless his soul. My second reaction is that we will continue to work for a free Palestinian state that's at peace with Israel."

Earlier in the day, a senior Palestinian official said Arafat had lapsed into a coma, and Palestinians in Paris delayed indefinitely a news conference scheduled for the morning, setting off a flurry of crisis sessions among officials in Ramallah and Israel.

"His situation is bad, but he is getting medical care," the former Palestinian information minister, Yasser Abed Rabbo, told al-Jazeera satellite television. "The situation is worrying."

Israeli Prime Minister Ariel Sharon gave permission last week for Arafat to be flown here for emergency care and diagnostic tests after the Palestinian leader had complained of nausea, stomach cramps and other ailments. Palestinian officials at first said he was suffering only from intestinal flu, but later conceded his condition was more serious.

After a few days of improvement, Arafat slipped in and out of consciousness on Wednesday and officials said he had deteriorated to the point where he had been transferred to an intensive care unit.

French President Jacques Chirac paid a 30-minute visit to the hospital Thursday afternoon and saw Arafat and his wife, "to whom he expressed his best wishes," Chirac's office said. The president also met with Palestinian officials and Arafat's medical team, "who are doing everything possible for the health of the president," according to Chirac's office.

As midnight approached, a few dozen Palestinians and sympathizers bearing flags and candles gathered outside the sealed-off hospital complex in a silent vigil.

"I am here because I need reassurance," said Noha Rashma, a 54-year-old Palestinian schoolteacher. "President Arafat is dying and I am here for him."

Anderson and correspondent Molly Moore reported from Jerusalem. Special correspondent Maria Gabriella Bonetti in Clamart, France, contributed to this report.

Slogan-chanting Palestinians rally in support of Yasser Arafat in the town of Beit Lahiya in the northern Gaza Strip. A young girl holds a candle near the entrance to the Percy military hospital southwest of Paris, where Arafat is being treated in the intensive care unit. French President Jacques Chirac visited Arafat at the hospital.