Original sentence: On 14 July 2009, the National Portrait Gallery started legal proceedings for breach of copyright against an editor-user of Wikipedia, who downloaded thousands of high-resolution images from the NPG website, and after a Wikipedia administer blocked the user account of a NPG lawyer alleging legal threats.The images were placed them on its sister media repository site, Wikimedia Commons
Edited sentence: On 14 July 2009, the National Portrait Gallery started legal proceedings for breach of copyright against an editor-user of Wikipedia, who downloaded thousands of high-resolution images from the NPG website, and placed them on its sister media repository site, Wikimedia Commons