Looks like this is the culprit's website http://www.nasimesabz.com/index.html There are links to her (4?) youtube accounts, which have all been terminated. There's a link to her instagram, which has also been terminated, however there is a cached-copy here http://www.pictame.com/tag/yesilnasim
As for the lady, she seems to genuinely believe in veganism and fitness. Whatever weird things she did to propagate that seemed to be working (330K views?!!).
Why she resorted to gun violence is much awaited.