On Thursday night, United Nations Secretary-General Antonio Guterres urged "an immediate halt to all hostile acts and any provocative actions" by Israel, Iran, and Syria "to avoid a new conflagration in the region." Early Thursday, in retaliation for a missile attack on the Golan Heights, Israel sent missiles and fighter jets into Syria, targeting "dozens" of Iranian assets as well as Syrian air-defense systems. The missiles left 23 dead, the Syrian Observatory for Human Rights said. This is the most serious escalation in long-simmering tensions between Iran and Israel in years. On Friday, Iranian Foreign Ministry spokesman Bahram Ghasemi criticized Israel's strike as a "fabricated and baseless" attack on Syria's sovereignty.

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