Hezbollah announced Wednesday that it launched a ballistic missile at Mossad headquarters near Tel Aviv, accusing the spy agency of assassinating its leaders and sabotaging its communication devices.

The move marked a new escalation in the conflict and triggered warning sirens in Israel's economic capital. The surface-to-surface missile, however, was reportedly intercepted by air defense systems after it was detected crossing from Lebanon, the Israeli military said.

There were no reports of damage or casualties and the military said there was no change to civil defense instructions for central Israel.

Warning sirens also sounded in other areas of central Israel, including the city of Netanya.

The Iranian-backed Hezbollah movement in Lebanon fired hundreds of missiles and rockets at Israel in recent days as months of conflict across the border with southern Lebanon has intensified sharply.

The Israeli military has been conducting its heaviest airstrikes of the war this week, targeting Hezbollah leaders and hitting hundreds of targets deep inside Lebanon that have killed more than 500 people and wounded more than 1,800.

On Tuesday, a strike in Beirut killed senior Hezbollah commander Ibrahim Kobeisi, who headed the group's missile and rocket force.