JERUSALEM — Syrian forces accidentally shot down a Russian military plane after an Israeli airstrike on Syrian territory, Kremlin officials said Tuesday, the worst case of friendly fire for Russia in the Syrian war.

The accident on Monday night briefly caused a crisis in Russia-Israel relations as the Kremlin blamed the Israelis, underscoring the risks of escalation from unintended consequences among the different forces operating in Syria.

All 15 Russian service members aboard were killed in the antiaircraft barrage that downed the plane, which had apparently been misidentified by Syrian gunners as Israeli.

Russia intervened in Syria three years ago to help President Bashar al-Assad prevail in a brutal civil war. The Russians have shown extraordinary tolerance toward Israel’s military, which has carried out more than 200 airstrikes over two years in Syria aimed at Iran-backed Shiite militias that Israel regards as a threat.