http://ru.krymr.com/a/28453755.html
http://ru.krymr.com/a/28452639.html
http://ru.krymr.com/a/28451032.html
A gunman killed an officer and a visitor after opening fire at an office of Russia’s Federal Security Service (FSB) in the far-eastern city of Khabarovsk on April 21, RT reported.
https://www.stratfor.com/situation-report/russia-gunman-opens-fire-fsb-office-khabarovsk
https://lenta.ru/articles/2017/04/18/machinegun/
http://ru.krymr.com/a/28431415.html
http://www.rbc.ru/newspaper/2017/04/14/58ef849a9a7947134a887f98
http://www.ng.ru/politics/2017-04-13/100_6974_opposition.html
http://ru.krymr.com/a/28427551.html