A Moscow teenager was hospitalized with a concussion and a broken leg after what parents said was an unmotivated beating by cops — though police said Thursday that he was not manhandled and likely inflicted the injuries himself. Sergei Vorotnikov, 17, was detained late Wednesday when talking to his beer-drinking friends on Ulitsa Marshala Biryuzova in northwestern Moscow, RIA-Novosti said, adding that the other teenagers fled the scene. […]