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.

Trump says Iran war deal close as Strait of Hormuz tensions linger
Two killed, 10 injured in Ukraine attack on Russia's border Bryansk region
Trump cancels US strikes on Iran, citing progress in talks
South Korea court sentences ex-President Yoon to 30-year jail term in drone case
Thai king's eldest daughter dies, aged 47, after long illness
US confirms third strike on Indian-crewed tankers this week
UK defence minister Healey quits, says PM Starmer's plans fail to keep country safe
False alarm at the Pentagon triggers brief shelter-in-place order
