Venezuelan President Hugo Chavez's breathing problems have worsened and he is suffering from a "severe" new respiratory infection as he struggles to recover from cancer surgery, the government said in a somber medical update on Monday.
The 58-year-old socialist leader has not been seen in public nor heard from in almost three months since undergoing the operation in Cuba. It was his fourth surgery since the disease was detected in mid-2011.
"Today there is a worsening of his respiratory function, related to his depressed immune system. There is now a new, severe infection," Information Minister Ernesto Villegas said, reading the latest brief statement on Chavez's condition.
Chavez made a surprise pre-dawn homecoming two weeks ago with none of the fanfare and celebration that had accompanied previous returns from treatment in Havana. The government said he is now fighting for his life at a Caracas military hospital. Armed guards are providing heavy security outside.
"The president has been receiving high-impact chemotherapy, along with other complementary treatments...his general condition continues to be very delicate," Villegas said.
Chavez suffered multiple complications after the December 11 surgery, including unexpected bleeding and an earlier severe respiratory infection that officials said had been controlled.
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The government said he had trouble speaking because he was breathing through a tracheal tube, but that he was giving orders to ministers by writing them down.
"The commander-president remains clinging to Christ and to life, conscious of the difficulties that he is facing, and complying strictly with the program designed by his medical team," Villegas said.
Chavez had undergone several grueling rounds of chemotherapy and radiation treatment, which at times left him bald and bloated. He twice wrongly declared himself cured.
The only sight of the former soldier since his latest operation were four photos published by the government while he was still in Havana, showing him lying in a hospital bed.
Following an emotional Mass at the military hospital on Friday, Vice President Nicolas Maduro - Chavez's preferred successor if he is unable to carry on as president - said the president had decided for himself several days earlier that he would return to Venezuela from Cuba.
Chavez was going to begin a "tougher and more intense" phase of his treatment, Maduro said, and he wanted to be in Caracas.
Maduro said that included chemotherapy - prompting some in the opposition to question whether chemotherapy can be successfully given to patients in such a delicate state.
The government is furious at rumors in recent days that Chavez might have died, blaming them on an opposition plot by "far-right fascists" to destabilize the OPEC nation, which boasts the world's biggest oil reserves.
"We call on all our people to stay alert, untouched by the psychological war deployed by foreign laboratories with the corrupt Venezuelan right, seeking to generate violence as a pretext for a foreign intervention," Villegas said.
"At this time, unity and discipline are the bases to guarantee political stability," he said, adding that the government was accompanying Chavez's children and other relatives in "this battle full of love and spirituality."
Opposition leaders have accused Maduro of repeatedly lying about the president's real condition. Several dozen anti-government student protesters have chained themselves up in public to demand proof that Chavez is alive and in Venezuela.
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"I can't even imagine the party they're going to have tomorrow with this news," pro-Chavez commentator Mario Silva said on state TV on Monday night. "But we all have to keep faith."
Should the Venezuelan leader step down or die, an election would be held within 30 days and would probably pit Maduro against opposition leader Henrique Capriles, who lost to Chavez in a presidential election in October.
The stakes are also high for the rest of Latin America. Chavez has been the most vocal critic of Washington in the region and has funded hefty aid programs for leftist governments from Bolivia to Cuba.