Iran and Israel traded fresh threats on Wednesday amid heightened concerns over how and when Tehran might retaliate for an Israeli strike in Syria last week that killed several senior Iranian commanders.

The leadership of Iran has repeatedly vowed to avenge the deadly April 1 strike on an Iranian Embassy building in Damascus. U.S. officials have said they were bracing for a possible Iranian response, and Israel put its military on alert.

Iran’s supreme leader, Ayatollah Ali Khamenei, reiterated threats of retribution in a speech he made on Wednesday for Eid al-Fitr, the holiday marking the end of the holy month of Ramadan. Attacking an embassy building, he said, “means that they have attacked our soil.”

“The evil regime made a mistake and it should be punished and will be punished,” he added, according to IRNA, the state news agency.

The response from Israel’s foreign minister, Israel Katz, was swift: “If Iran attacks from its territory, Israel will react and attack in Iran,” he wrote in Farsi on X.

Israel has not publicly taken responsibility for the strike in Damascus, but several Israeli officials have confirmed its involvement to The New York Times.

Analysts have cautioned that while both sides probably want to avoid open war, any miscalculation could spill over and lead to a broader regional escalation.

Israel has been trading fire with Iran-backed militant groups since the Hamas-led attack on Oct. 7 ignited the war in Gaza.