Spanish nongovernmental organization (NGO) Open Arms said it and U.S. charity World Central Kitchen (WCK) were suspending attempts to get aid to Gaza via sea after seven WCK workers were killed in an Israeli airstrike on Monday.

The two charities had worked together in launching a maritime corridor of humanitarian aid to Gaza from Cyprus in March, and had just completed unloading about a third of the shipped cargo when the convoy of WCK workers was attacked on April 1.

“This attack, perpetrated by the Israeli Defence Forces last Monday, marks a painful turning point in our efforts to alleviate the humanitarian crisis in Gaza,” Open Arms said in a written statement.

WCK has said it is pausing its work in the besieged enclave, where it had been operating with more than 60 community kitchens since October. The U.N. has said famine is an imminent threat to more than half of Gaza’s population.

On Wednesday about 240 metric tons of food returned to Cyprus in a ship convoy led by the Open Arms’s salvage ship after the offloading operation was halted in the wake of the killings.

“With the arrival yesterday of the Open Arms ship in Larnaca, Cyprus, the mission in alliance with WCK in the humanitarian corridor to the Gaza Strip is suspended,” Open Arms said.

It quoted Open Arms director Oscar Camps calling Gaza a “dystopian laboratory where people’s blood flows while war technologies are tested and perfected, directed by increasingly automated algorithms that allow all human responsibility to be diluted, using technology and trivializing evil.”

“Now states are rushing to extend their condolences to the families, but they are not showing the same rush to stop the shipment of weapons to this laboratory of destruction,” Camps said.

“How much more humanity must be lost in this genocide?”