Iran's consulate in the Syrian capital Damascus was flattened on Monday in what Syrian and Iranian media described as an Israeli air strike.
A Lebanese security source, speaking to Reuters, said one of the dead was Mohammad Reza Zahedi, a senior commander in Iran's Revolutionary Guards Corps (IRGC). Iranian state television said several Iranian diplomats had been killed.
Israel, which has repeatedly hit Iranian targets during the six-month war in Gaza, declined to comment on the incident, following its usual practice.
An Israeli military spokesperson said: "We do not comment on reports in the foreign media."
Iran's Tasnim news agency said five people were killed in the Israeli strike. Syria's SANA state news agency reported an unspecified number of deaths and injuries.
Since the Palestinian group Hamas' attack on Israel on October 7, Israel has ramped up airstrikes in Syria against Lebanon's Hezbollah militia and Iran's Guards, both of which support the government of President Bashar Al Assad.
Israeli planes and tanks pounded areas across the Gaza Strip overnight and on Sunday, destroying several residential buildings, witnesses said, as Palestinians desperately awaited implementation of a US plan to end the war.
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