On Wednesday night, Villegas went on television to give an update, saying Chavez was in "stable condition." Reading from a statement, he said Chavez was with his close relatives and said the government invited people to "accompany President Chavez in this new test with their prayers."
Ecuadorean President Rafael Correa also acknowledged the possibility of losing his close ally, while wishing him the best. "Chavez is very important for Latin America, but if he can't continue at the head of Venezuela, the processes of change have to continue," Correa said.
Maduro looked sad as he spoke on television, his voice hoarse and cracked at times after meeting in the pre-dawn hours with Cabello and Ramirez. The pair returned to Venezuela about 3 a.m. after accompanying Chavez to Cuba for his surgery.
"It was a complex, difficult, delicate operation," Maduro said. "The post-operative process is also going to be a complex and hard process."
Without giving details, Maduro reiterated Chavez's recent remarks that the surgery presented risks and that people should be prepared for any "difficult scenarios, which can be faced only with the unity of the people." Still, he expressed optimism Chavez would return home.
The vice president criticized the opposition, accusing it of using Chavez's illness to attack him. Many political adversaries have said the president should be more forthcoming about details of his pelvic cancer.
The dramatic events of this week, with Chavez suddenly taking a turn for the worse, had some Venezuelans wondering whether they were being told the truth because just a few months ago the president was running for his fourth presidential term and had said he was free of cancer.
Lawyer Maria Alicia Altuve, who was out in bustling crowds in a shopping district of downtown Caracas, said it seemed odd how Maduro wept at a political rally while talking about Chavez.
"He cries on television to set up a drama, so that people go vote for poor Chavez," Altuve said. "So we don't know if this illness is for that, or if it's that this man is truly sick."
Chavez announced over the weekend that he needed to have surgery again after tests showed "some malignant cells" had reappeared in the same area of his pelvic region where tumors were previously removed.
Throughout his nearly 14-year-old presidency, Chavez has been loved by some Venezuelans and reviled by others as he has nationalized companies, crusaded against U.S. influence and labeled his enemies "oligarchs" and "squalid ones."
Some Chavez supporters said they find it hard to think about losing the president and are worried about the future.
Others Venezuelans said that while they're sorry about Chavez's health and wish him the best, it isn't a particular concern for them. Many were out buying Christmas gifts and food as they prepared for the holiday season.
"The truth is that I have not paid much attention to the news. I just know the president is very sick and he went to Cuba for an operation," said Gabriela Hernandez, a nurse and opposition supporter. "I hope that he can get better. ... I don't wish for misfortune for anybody."
Omar Mendez, a shopkeeper who said he doesn't support Chavez or the opposition, was among several who worried about the possibility of political upheaval if Chavez doesn't survive.
"Many people don't dare to say it, but they want Chavez's death," Mendez said. "I would say something to those people: They should think hard about the consequences if Chavez does not survive this terrible illness because Chavez's death could bring about an unprecedented political crisis."
Associated Press writer Christopher Toothaker contributed to this report.
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