Caracas:
Venezuela's President Hugo Chavez lost his battle with cancer on Tuesday, his death silencing the leading voice of the Latin American left and plunging his oil-rich nation into an uncertain future.
Vice President Nicolas Maduro, who struggled to stifle tears as he announced Chavez's passing, said the government had deployed the armed forces and police "to accompany and protect our people and guarantee the peace."
Venezuela, still divided after a close-run election in October last year, declared a week of national mourning, and a senior minister said a new poll would be called within what are sure to be 30 tense days.
Foreign Minister Elias Jaua said the 58-year-old Chavez's hand-picked successor Maduro would take over as interim leader pending the next election, declaring: "It is the mandate that comandante President Hugo Chavez gave us."
International reaction was mixed, with many in Latin America and beyond hailing Chavez's support for the poor but others expressing the hope that the iconic figure's passing would lead to a more open political system.
Venezuela's closest ally, communist Cuba, declared its own mourning period for a leader who helped prop up their island economy with cheap fuel and cash transfers, and dubbed Chavez a "true son" of revolutionary Fidel Castro.
But US President Barack Obama -- often the target of Chavez's anti-American scorn -- was circumspect, pledging the United States would support the "Venezuelan people" and describing Chavez's passing as a "challenging time."
"As Venezuela begins a new chapter in its history, the United States remains committed to policies that promote democratic principles, the rule of law, and respect for human rights," Obama said in a short written statement.
Shortly before Chavez's death was announced, senior officials had accused Venezuela's enemies of somehow giving the firebrand leftist the cancer that eventually killed him, and two US military attaches were expelled.
Chavez was showered with tributes by Latin American leaders, not just his leftist allies but also world figures like Brazil's Dilma Rousseff, who hailed him as a "great Latin American" and "a friend of the Brazilian people."
Die-hard Chavista partisans gathered in Caracas' Plaza Bolivar -- named after the independence hero whose legacy Chavez co-opted for his Bolivarian Revolution -- weeping, waving portraits and chanting his name.
"He was a man who taught us to love our fatherland," said 40-year-old municipal worker Francis Izquierdo. "The comandante is physically gone but he remains in our hearts and we must continue building the fatherland."
Soldiers brought the Venezuelan flag down to half-staff at a Caracas military hospital, where senior figures in Chavez's 14-year-old administration gathered before the cameras of state television as Maduro break the news.
"Long live Chavez!" the officials shouted at the end of his announcement.
Defense Minister Diego Molero, surrounded by top military officers, said the armed forces would defend the constitution and respect Chavez's wishes.
Chavez had checked into the hospital on February 18 for a course of chemotherapy after spending two months in Cuba, where in December he had undergone his fourth round of cancer surgery since June 2011.
The once ubiquitous symbol of Latin America's "anti-imperialist" left disappeared from public view after he was flown to Cuba on December 10, an unprecedented absence from the public eye that fueled all manner of rumors.
The government had sent mixed signals about the president's health for weeks, warning one day that he was battling for his life, yet insisting as recently as last weekend that he was still in charge and giving orders.
And the opposition repeatedly accused the government of lying about the president's condition.
A new election could offer another shot at the presidency to Henrique Capriles, the opposition leader who lost to Chavez in October. He took to Twitter to call for unity.
"My solidarity is with the entire family and followers of President Hugo Chavez, we call for Venezuelan unity at this moment," Capriles wrote.
Chavez will be mourned by many of the country's poor, who revered the self-styled revolutionary for using the country's oil riches to fund popular housing, health, food and education programs.
And like-minded Latin American leaders like Cuba's Raul Castro, Ecuador's Rafael Correa and Bolivia's Evo Morales lost a close friend who used his diplomatic muscle and cheap oil to shore up their rule.
Chavez died five months after winning re-election, overcoming public frustration over a rising murder rate, regular blackouts and soaring inflation.
The opposition had accused Chavez of misusing public funds for his campaign and dominating the airwaves while forcing government workers to attend rallies through intimidation.
He missed his swearing-in for a new six-year term on January 10, but the Supreme Court approved an indefinite delay.
First elected in 1998, Chavez had since worked to consolidate his power and make his revolution "irreversible."
But his policies drove a wedge into Venezuelan society, alienating the wealthy with expropriations while wooing the poor with social handouts.