By Simon Lewis and Humeyra Pamuk WASHINGTON (Reuters) -The United States has assessed that members of Russia’s forces have committed war crimes in Ukraine, U.S. Secretary of State Antony Blinken said on Wednesday, adding that Washington’s conclusion was based on a “careful review” of available information from public and intelligence sources. Blinken said there had been “numerous credible reports of indiscriminate attacks and attacks deliberately targeting civilians, as well as other atrocities” by Russia’s forces in Ukraine, specifying attacks in the besieged city of Mariupol. Russia has deni…