BEIRUT - Images of Iran's Supreme Leader Ayatollah Ali Khamenei appearing frail and in bed have raised questions about the seriousness of his condition, and who might eventually succeed him.
In early September, Khamenei made a surprise announcement that he was having surgery and asked people to pray for his health. What followed was unprecedented in the 35-year history of the Islamic Republic.
Top officials including President Hassan Rouhani, the head of the judiciary and the speaker of parliament went to the 75-year-old Supreme Leader's bedside, with each visit reported with photos on Iranian news sites.
Even former president Mahmoud Ahmadinejad, who has had a tense relationship with Khamenei in recent years, came for a visit.
Rumours about Khamenei have circulated for years. But there has never been such a media blitz on the health of the Supreme Leader, who holds substantial influence or constitutional authority over the executive, legislative and judicial branches of government as well as the military and media.
The head of the surgical team said Khamenei had an operation on his prostate which lasted less than half an hour and only local anesthetic had been used. He was completely awake and speaking during the procedure, the surgeon said.
But if Khamenei's health deteriorates, the traditional clergy and the Islamic Revolutionary Guard Corps - Iran's top military force and an economic powerhouse - will need to settle on a successor quickly if the country is to avoid a period of political instability, experts say.
"The illness of leaders in undemocratic countries is seen as a national security issue," said Mehdi Khalaji, a former senior fellow at the Washington Institute for Near East Policy who is now the CEO of the Idea Center for Arts and Culture.
TUSSLE IN STORE
So far, Iran has had only two Supreme Leaders since the 1979 revolution, with Khamenei succeeding the Islamic Republic's founder Ayatollah Ruhollah Khomeini in 1989.
Supreme Leaders are elected by the Assembly of Experts, which is made up mostly of the clerical old guard. But it is clear that the Revolutionary Guards will also play a major role, experts say.
In the past year, the Revolutionary Guards have pushed back hard against attempts by the Rouhani government to curb their influence on economic and foreign policy as well as the country's disputed nuclear programme, the subject of negotiations between Iran and international powers.
Neither will they be easily sidelined on talks about a future Supreme Leader. "It's unlikely that the Revolutionary Guards will defer to a group of geriatric clerics regarding their next commander in chief," said Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace.
Ali Ansari, director of the Institute of Iranian Studies at the University of St. Andrews, predicted problems with the succession. "I don't think it's going to be smooth, whatever happens," he said.
"There will be a tussle." Khamenei was an unexpected choice after Khomeini's death because he had not been seen as a senior cleric. But over the past 25 years he has solidified his grip on power, largely by gaining the support of the Revolutionary Guards.