U.S. cybersecurity firm CrowdStrike has revised and retracted statements it used to buttress claims of Russian hacking during last year's American presidential election campaign. The shift followed a VOA report that the company misrepresented data published by an influential British think tank. In December, CrowdStrike said it found evidence that Russians hacked into a Ukrainian artillery app, contributing to heavy losses of howitzers in Ukraine's war with pro-Russian separatists. VOA reported Tuesday that the International Institute for Strategic Studies (IISS), which publishes an annual reference estimating the strength of world armed forces, disavowed the CrowdStrike report and said it had never been contacted by the company. Ukraine's Ministry of Defense also has stated that the combat…