evidence: Russia boasted of blowing up an advanced Ukrainian tank. Video shows it was a tractor [...] Tank crews operating at the front lines typically conceal themselves in vegetation or behind buildings, emerging only to move and shoot, two experts in military vehicles told the AP. It would be highly unusual for tanks to be parked in the open, where they make easy targets for enemy gunners, they said. [...] "The silhouette of that particular vehicle or object did not look commensurate with what I’d be expecting for a Leopard tank," said George Barros, who leads the Geospatial Intelligence Team for Russia and Ukraine at the Washington-based Institute for the Study of War. "I agree ... that it was probably a piece of heavy farm equipment."