Israeli naval forces recently released an unidentified white substance during their interception of Madleen, an aid vessel bound for Gaza containing humanitarian activists such as Greta Thunberg. Witnesses on board reported experiencing burning sensations, coughing fits and temporary vision issues after coming in contact with it.

The Madleen, part of the Freedom Flotilla Coalition, was interdicted early Monday while on its way to Gaza with medical supplies, baby formula and other essential goods. According to activists aboard, as Israeli commandos approached, drones flew overhead dispensing white powdery or mist-like substances across its deck.

“Suddenly we were engulfed by buzzing drones, then this white spray descended,” reported Anisa Qassem of Norway as she volunteers. It burned their eyes and throats; some even choked – we don’t yet know what caused this phenomenon.”

Footage shared by activists and confirmed by multiple independent journalists shows clouds of white material descending onto a ship moments before Israeli forces boarded it, prompting activists to cover their faces and crouch low as it settled on board.

Israeli Defense Forces (IDF) have not officially confirmed what substance was employed; only that “non-lethal crowd control measures” were deployed according to protocol in order to ensure safe boarding was completed. There have been no further details provided regarding this matter.

Medical professionals affiliated with the flotilla have expressed concerns, noting that several activists suffered skin irritation and breathing issues after exposure. “These symptoms point to chemical irritation; unfortunately we weren’t immediately able to pinpoint it,” explained Dr. Mahmoud Faris, one of the physicians onboard the ship. To accurately pinpoint exactly what was used onboard we need laboratory testing done before conducting further action.

Human rights groups have demanded an independent investigation of this incident. Amnesty International issued a statement demanding greater transparency: “Israel must disclose any chemical agents used against peaceful activists on international waters as soon as possible in order to assess any potential health impacts and the nature of any possible health consequences.

Legal experts have also provided insight, questioning whether the deployment of such substances constitutes a violation of maritime law. Professor Lina Roemer, an expert in international humanitarian law said “chemical exposure without warning may violate various international conventions”.

The Freedom Flota Coalition has promised to seek answers and accountability, accusing Israel of using unjustifiable force and intimidation tactics against civilians delivering aid.

On Tuesday, activists from Madleen were receiving medical checkups and samples were being sent for independent testing, while global calls for transparency grew exponentially – critics demanded Israel disclose exactly what had been sprayed-on them and why.