Israel has bombed an Iranian diplomatic facility in Syria in a strike that killed a top Islamic Revolutionary Guard Corps commander, according to Iran’s state media.

“[Israel has] gone beyond the red line,” Iranian Ambassador to Syria Hossein Akbari said Monday on an Iranian state media broadcast. “Iran has never left any crimes of the Zionist regime without an answer. So, definitely, the Zionists and their allies know that in proportion to the crime they have committed, they need to await a proper response on the basis of Iran’s choosing at the right place and time.

The strike was announced by Syrian state media. Iran has announced that Brig. Gen. Mohammad Reza Zahedi, identified as the commander of the IRGC Quds Force for Syria and Lebanon, died in the bombardment. Israel has targeted Iranian forces in Syria numerous times in the years since Iran deployed forces to prop up Syrian dictator Bashar Assad, but the destruction of a diplomatic facility is unusual.

“The exact number and names of those killed will be published following the clearing-out of the rubble,” the Iranian Embassy in Lebanon said, according to a Jerusalem Post translation. 

Secretary of State Antony Blinken’s team declined to confirm reports that Israel gave the United States a last-minute notification of the impending strike.

“We are in conversations with partners in the region, gathering more information,” State Department spokesman Matthew Miller told reporters. “But at this point, we don’t have confirmation either of the target or the responsible party.”