Israel said Sunday that Iran launched missiles at it in the first such bombardment since a fragile ceasefire took effect in early April, complicating mediation efforts for a deal to end the war.

Iran’s state broadcaster confirmed the launches. Tehran had warned of retaliation after Israel struck Beirut’s southern suburbs without warning earlier Sunday in defiance of Washington’s request days ago to stand down. Israel called it retaliation for the Iranian-backed Hezbollah firing at northern Israel earlier in the day.

“Should these acts of aggression be repeated, the responses will be broader in scope and will encompass all American and Zionist targets throughout the region,” Iran’s Revolutionary Guard said in a statement that also referenced attacks on Iran’s coast and vessels around the Strait of Hormuz.

Israel’s military said it intercepted the missiles, and less than an hour later it said people could leave shelters but stay near them. Sirens sounded in several areas of the country. Multiple explosions were heard in northern Israel.

“Iran has made a grave mistake,” Israel military spokesman Brig. Gen. Effie Defrin said.