It was barely 8am in the sweltering centre of Havana when the small group of workers gathered to offer support for their ailing President. The speeches they heard were short and fierce, the slogans they chanted had been learnt by heart. "Viva la revolucion," they shouted. "Viva Fidel! Our country or death. We will overcome."
People have been predicting the demise of Cuba's 79-year-old leader for almost the entirety of his near half-century in power, a rule that has been condemned by critics for its brutality to his opponents but celebrated by his supporters for its defiance of the US. But yesterday morning the question of Cuba's political future took on great uncertainty as the country awoke to the news that their leader had undergone intestinal surgery and - for the first time in those 47 years of exercising total power - temporarily ceded control to his brother, Raul.
"We are here to wish him well for his health," said Rafael Ceruto, one of the speakers who addressed the crowd. "At the moment everything is normal." Like the others who spoke in front of a statute of Jose Marti, a revolutionary hero from the 19th century, Mr Ceruto insisted that the President's surgery was not a serious setback and that he would be recuperating for a few weeks. This too, was the opinion of most Cubans, who have grown up with stories of their leader's extraordinary vitality. Such expressions of solidarity are to be expected in Havana, where living with police surveillance is a way of life and dissident political expression can lead to a jail sentence.
Likewise this was the official narrative, as reported on the front page of the state-run newspaper, Granma, which carried a proclamation purportedly from the President, which said he had over-exerted himself travelling to a summit in Argentina.
"This caused an acute intestinal crisis with sustained bleeding that obliged me to face a complicated surgical operation," his statement said. "The operation obliges me to remain for several weeks resting."
News of the leader's ailment and his passing to his 75-year-old brother control of the Communist Party, the post of commander-in-chief of the armed forces and president of the executive council of state, had been announced the previous evening, when Mr Castro's "proclamation" to the people had been read on television by his secretary.
In the capital, the response was muted. Walking through the streets of Old Havana, people outwardly expressed minimal concern. "I think he will be all right," Flora Gomez Prado, 71, said. She was just 24 when Castro, Che Guevara and others overthrew Fulgencio Batista and seized control of the country.
Privately, though, some people may be thinking differently as they reflect that their leader is set to celebrate his 80th birthday on 13 August and that this medical problem is just the latest sign of his increasing frailty. Certainly, the newspaper vendor who had sold me a copy of Granma the previous morning was more circumspect. Mr Castro was not a child, he nodded. "Fidel is 79 years old."
By contrast, a couple of hundred miles away in Miami's Little Havana, home to thousands of anti-Castro Cuban exiles and the epicentre of political power that drives America's economic embargo against Cuba, the reaction could barely have been more different. Thousands poured into the streets, cheering. They hoped that this was the sign that things were about to change.
But who knows? It is not easy predicting the future in a country where free speech is outlawed and political dissent is repressed. A total of 75 dissidents were jailed in 2002 and Amnesty International has reported that some political prisoners have been held in isolation cells for months. And who would write off Fidel Castro? He has repeatedly survived the best US efforts to dislodge him, seeing off invasion forces and avoiding assassination attempts. President George Bush tightened the embargo and established an $80m (£42m) fund to "promote democracy" on Cuba.
His stamina is legendary. Though in 2001 he fainted from heat exhaustion while delivering a speech and in 2004 he broke his knee-cap and right arm in a fall, he last week gave a Revolution Day speech in which he taunted Mr Bush. While admitting that he might not be leader when he is 100, he celebrated his country's achievements.
Despite this there are signs that the Cuban government has prepared for a transition and Raul has long been the anointed successor. While Mr Castro is the world's longest serving head of government and third-longest head of state, his brother is the world's longest-serving defence minister, and presumably the longest successor-in-waiting.
Some observers say the transition is already under way. Brian Latell, a former CIA Cuba analyst, points to recent media features about Raul, as though the state apparatus is preparing Cubans for a switch.
"Signs of what is probably succession planning at the highest levels of the Castro regime have been multiplying," Mr Latell wrote in June. "These developments could even indicate that Raul has already assumed responsibilities."
Some writers on Cuba predict that little change is in store. That may underestimate the importance of Mr Castro. While his presence may not be as ubiquitous as it once was, it is hard to travel around Havana without being confronted by his image.
One banner hanging from a wall in anticipation of his birthday, says: "Viva Fidel. Eighty more years." He remains an icon to leftists. It is possible, if not likely, that Mr Castro's longevity - in terms of politics as well as his health - has been helped by the US policy.
That was the message Mr Castro sent to his people. "I don't have the slightest doubt that our people and our Revolution will fight until the last drop of blood to defend these and other ideas and measures that may be necessary, to safeguard this historic process," he said. "Imperialism will never crush Cuba."
Extract of a letter from Fidel Castro read on state television by Carlos Valenciaga, his secretary:
Days and nights of continuous work with hardly any sleep have caused my health, which has withstood all tests, to fall victim to extreme stress and to be ruined.
This has caused an acute intestinal crisis with sustained bleeding that has obliged me to undergo a complicated surgical operation. The operation will force me to take several weeks of rest away from my duties.
The 80th anniversary of my birthday, which thousands of people so generously agreed to celebrate next 13 August, I ask that it be postponed for 2 December of this year, the 50th anniversary of the landing of the Granma.
I do not have the slightest doubt that our people and our revolution will fight to the last drop of blood to defend these and other ideas and measures that are necessary to safeguard this historic process.
Imperialism will never be able to crush Cuba.
The Battle of Ideas will continue.
Long live the fatherland!
Long live the revolution!
Long live socialism!
Always toward victory!
Fidel Castro Ruz, Commander in Chief. First Secretary of the party and President of the Councils of State and of Ministers of the Republic of Cuba.Reuse content