Syria walks a diplomatic tightrope between Israel and Iran, trying to avoid entanglement while war unfolds in its airspace.

Israel said on Saturday it had killed a veteran Iranian commander during attacks by both sides in the more than week-long air war, while Tehran said it would not negotiate over its nuclear program while under threat.

Israel’s sophisticated air defense system has in the past fended off attacks from Gaza, Lebanon, Iraq, Syria, Yemen and Iran. Still, Iranian missiles have tested the multilayered network, and some projectiles have made impact.