Iran reiterated its pledge to punish Israel on Friday at a funeral for seven officers killed in a suspected Israeli airstrike on the Iranian embassy compound in Syria this week.
State television showed demonstrators carrying pictures of those killed and banners with slogans such as "Death to Israel" and "Death to America".
The dead included one of Iran's top soldiers, Brigadier General Mohammad Reza Zahedi, a senior commander in the Islamic Revolutionary Guard Corps (IRGC) who was visiting the Iranian embassy compound in the Syrian capital Damascus on Monday.
Former Guards commander Mohsen Rezaei, commenting on the possibility of retaliation against Israel, said: "The decision has been made. It will definitely be implemented," according to the semi-official Tasnim new site. He did not elaborate.
The funeral coincided with the annual Quds (Jerusalem) Day, during which Iran stages large state-sponsored pro-Palestinian and anti-Israel rallies nationwide.
The airstrike was the boldest, and deadliest attack in a series that have killed Iranian officials in Syria since December.
Iran warned of harsh retaliation, raising the spectre of a wider war and prompting the Israeli armed forces to suspend leave for all combat units on Thursday, a day after they said they were mobilising more troops for air defence units.
Israeli Prime Minister Benjamin Netanyahu said on Thursday his country would harm "whoever harms us or plans to harm us".
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