WASHINGTON - The United States and partner nations are carrying out the first air strikes against Islamic State targets in Syria, the Pentagon said on Monday, in ongoing operations that mark the opening of a new, far more complicated front in battle against the militants.

"I can confirm that US military and partner nation forces are undertaking military action against ISIL terrorists in Syria using a mix of fighter, bomber and Tomahawk Land Attack Missiles," Rear Admiral John Kirby, Pentagon press secretary, said in a statement.

"Given that these operations are ongoing, we are not in a position to provide additional details at this time."

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