U.S. officials released satellite images Sunday they say offer proof that Russian forces have been shelling eastern Ukraine in a campaign to assist rebel groups fighting Ukraine’s government in Kiev. Obama Administration officials said as early as last week that the Russians were launching attacks in eastern Ukraine.

The U.S. Office of the Director of National Intelligence, which released the civilian-taken satellite images Sunday, said they show visual evidence that Russia has been firing shells across the border at Ukrainian military forces. Officials also said the images show that Russia-backed separatists have used heavy artillery, provided by Russia, in attacks on Ukrainian forces from inside Ukraine.

One image dated July 25–26 shows what DNI claims is “ground scarring” on the Russian side of the border from artillery aimed at Ukrainian military units in Ukraine, as well as the resultant ground craters on the Ukrainian side of the border:

A slide from a day earlier is said to show self-propelled artillery on the Russian side of the border oriented toward Ukraine, with impact areas near Ukrainian military units:

Russian officials denied on Friday allegations of involvement in eastern Ukraine, calling it a U.S.-led “smear campaign,” the New York Times reports.

The Ukrainian military said Saturday it was poised to reclaim Donetsk, the city at the heart of the pro-Russian insurgency, even as Russian forces numbering around 15,000 amassed on the border, the Washington Post reports.

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