Damascus, Syria (CNN) -- Concern about the possibility of broader war in the Middle East grew Monday after reported airstrikes on Syrian military installations. The reported strikes killed 42 Syrian soldiers, the opposition Syrian Observatory for Human Rights said Monday, citing medical sources. It said 100 people remained missing. The Syrian government warned Sunday's apparent strikes -- which followed one last week that Syria also blames on Israel -- "opens the door wide for all the possibilities." Syrian ally Iran warned of a "crushing response" while Russia called reports of Israeli involvement "very worrying." But an Israeli general who commands forces on the Syrian border said "there are no winds of war," according to the Israel Defense Forces website.
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NEW: Syrian prime minister: Israeli "aggressions ... have left no room for hesitation"
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There is no information suggesting rebel use of sarin, a State Department official says
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Israel conducted airstrikes in Syria on Sunday and last week, a U.S. official tells CNN
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Reports of Israeli strikes are "very worrying," the Russian Foreign Ministry says
Iran said it will stand by @placeholder, "and if there is need for training, we will provide them with necessary training," Brig.