The foreign ministry has requested that the investigation into the attack on NGO World Central Kitchen (WCK) staff in Gaza be swift, thorough and accountable, Foreign Minister Constantinos Kombos said on Thursday.

Kombos’ statements come after three ships carrying humanitarian aid returned, with most of their cargo still on board, to the Larnaca and Limassol ports Wednesday evening.

In total, 240 tonnes of the 332 tonnes which were sent from Cyprus on Saturday returned to the island with the ships.

A total of seven aid workers were killed on Monday night when Israel carried out an airstrike on three vehicles belonging to WCK, which had been distributing the aid sent from Cyprus.

Earlier, WCK founder chef Jose Andres said the Israeli attack was not a mistake.

Kombos said he had communicated on Wednesday night with Andres and conveyed the deepest condolences of the Cyprus government “for the tragic loss of seven fearless heroes of humanity who were helping people on the ground”.

“Dear Jose, we mourn with you. We are working closely with the World Central Kitchen team and share the pain this tragedy has caused the World Central Kitchen family,” Kombos said.

He added that Cyprus “strongly condemns all acts of violence against of humanitarian workers, who must always be protected, in accordance with international humanitarian law”.

“The investigation must be swift, thorough and accountable,” he concluded.

On Thursday, the WCK made fresh statements, calling on the governments of Australia, Canada, the United States, Poland, and the United Kingdom “to join us in demanding an independent, third-party investigation into these attacks”.

This investigation, they said, must “include whether they were carried out intentionally or otherwise violated international law”.

They added that they had requested that the Israeli government immediately preserve all documents, communications, video and audio recordings, and any other materials potentially relevant to the April 1 attacks.

“An independent investigation is the only way to determine the truth of what happened, ensure transparency and accountability for those responsible, and prevent future attacks on humanitarian aid workers,” they added.