The body of 48-year-old founder of White Helmets, ex-British serviceman James Le Mesurier was found on a street in Istanbul on Monday, reports TASS, citing NTV.

Police interviewed Le Mesurier’s widow with whom he was living in Istanbul, and she reported that her husband had taken a sleeping pill while she was sleeping. Police examined the video tapes and saw that strangers hadn’t entered the building at night.

CNN Turk reports that cuts were seen on Le Mesurier’s face and body and that his extremities were fractured. Investigators currently think Le Mesurier died after falling from the apartment window or balcony.

The White Helmets organization was established in 2014 in Syria and became popular after posting photos and videos of the destruction caused by the Syrian government’s assaults and the victims on the Internet. Moreover, the organization has been blamed for falsifying the materials several times.