A ship carrying supplies bound for the Gaza Strip was attacked by Israeli drones in international waters on Friday, according to the activist group that organized the flotilla. The vessel reportedly took at least one direct hit to its hull and sustained damage from fire, forcing its crew to issue an urgent call for help.

Organizers with the Freedom Flotilla Coalition (FFC) said one of their vessels was attacked by an unidentified drone in the early hours of Friday morning, noting the ship was not far off the coast of Malta when it was hit.

"At 00:23 Maltese time, the Conscience, a Freedom Flotilla Coalition ship, came under direct attack in international waters," the group said in a press release. "Armed drones attacked the front of an unarmed civilian vessel twice, causing a fire and a substantial breach in the hull. [. . .] The drone strike appears to have deliberately targeted the ship's generator, leaving the crew without power and placing the vessel at great risk of sinking."

An FFC spokesperson, Caoimhe Butterly, later told Reuters that the ship was struck en route to Malta, where it was scheduled to pick up other activists, among them climate campaigner Greta Thunberg and retired US Army Colonel Mary Ann Wright. The group said it had arranged the aid shipment "under a media black out to avoid any potential sabotage."

The FFC also shared footage which allegedly shows the aftermath of the strike, with smoke and flames seen on the ship. At one point in the brief video, an apparent explosion can be heard.

In a second press release, the group later shared a photo of the damage sustained in the strike.

Maltese authorities said they received an SOS call from a vessel in international waters soon after midnight local time, adding that a nearby tugboat assisted the ship, according to Reuters. Officials added that the crew of the Conscience declined to board the tugboat, and also confirmed to CNN that the fire on the ship had been extinguished. No casualties have been reported in the attack.

The FFC press release added that "Israeli ambassadors must be summoned and answer to violations of international law, including the ongoing blockade [on Gaza] and the bombing of our civilian vessel in international waters."

In a social media post early on Friday, the United Nations special rapporteur on the occupied Palestinian territories, Francesca Albanese, said she "received a distressed call from the people of the Freedom Flotilla that is carrying essential food and medicine to the starving Gaza population."

"I call on concerned state authorities, including maritime authorities, to support the ship and its crew as needed. I trust the competent authorities will also ascertain the facts and intervene appropriately," she added.

The Israeli military has yet to comment on the incident, but said it was looking into reports about the attack, according to the BBC. Israel's Foreign Ministry did not immediately respond to a request for comment by Reuters.