The U.S. is ramping its criticism of Russia over its support for the Assad regime in Syria.

FOX's Rachel Sutherland reports from Washington:

Secretary John Kerry says Russia and Syria should face a war crimes investigation for their attacks on Syrian civilians after Syrian forces struck another hospital overnight, killing 20 people and wounding another 100:

(Kerry) "Russia and the regime owe the world more than an explanation about why they keep hitting hospitals and medical facilities and children and women."

Secretary Kerry said the attacks are way beyond accidental at this point, and he accuses Russia and Syria of undertaking a targeted strategy to terrorize civilians.

In Washington, Rachel Sutherland, FOX News.

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