The body of 43-year-old James Le Mesurier was found Monday in the Beyoglu district of the city, with state-run Anadolu news agency reporting that he may have fallen to his death.

The White Helmets, a roughly 3,000 member NGO formally known as the Syrian Civil Defense, was established in Turkey in "late 2012 - early 2013" Le Mesurier trained an initial group of 20 Syrians. The group then received funding from Le Mesurier's Netherlands-based non-profit group, Mayday Rescue - which is in turn funded by grants from the Dutch, British, Danish and German governments.