Attacks on aid workers are not just something that happens in war, Prime Minister Justin Trudeau said Thursday, slamming Israeli Prime Minister Benjamin Netanyahu鈥檚 defence of a deadly airstrike on aid workers in central Gaza on April 1.

Canadian Army veteran Jacob Flickinger, 33, was among those killed while delivering food aid for World Central Kitchen.

Netanyahu said Wednesday the blasts were a tragic accident that will be investigated 鈥� but also a consequence of armed conflict.

鈥淭his happens in war,鈥� Netanyahu said.

At a news conference in Winnipeg Thursday, Trudeau said he had to 鈥渄irectly take issue鈥� with those comments.

鈥淣o, it doesn鈥檛 just happen,鈥� Trudeau said. 鈥淎nd it shouldn鈥檛 just happen when you have aid workers for an extraordinary organization like World Central Kitchen risking their lives every day in an incredibly dangerous place to deliver food to people who are experiencing a horrific humanitarian catastrophe.鈥�

World Central Kitchen is demanding a full independent investigation into the attack that killed its workers, including Flickinger, a Palestinian driver, and citizens of Australia, Poland and the United Kingdom.

They were in a clearly marked aid convoy after delivering 100 tonnes of food to a warehouse in central Gaza when they were hit.

Trudeau said a 鈥渇ully open, transparent, independent and rapid investigation鈥� is absolutely required.

But he said a ceasefire and a massive influx of humanitarian support is also critical.

鈥淭he reality is we need much more humanitarian support to flow into Gaza, much more protection of civilians, of innocents and of aid workers,鈥� he said.

鈥淭hat鈥檚 why we need a humanitarian ceasefire. We need for Hamas to lay down its arms. We need for the hostages to be released, and we need a ceasefire to allow this humanitarian catastrophe to end as quickly as possible.鈥�

International reaction to the deadly airstrikes has been swift and biting at a time when Israel was already facing sharp criticism for the humanitarian toll of its war in Gaza.

U.S. President Joe Biden is scheduled to speak by phone with Netanyahu Thursday. The U.S. has been one of Israel鈥檚 biggest defenders and earlier this week approved the transfer of additional bombs to the Israeli military.

But Biden has been getting increasingly frustrated with Israel over the humanitarian catastrophe in Gaza, including the limited aid Israel is allowing in and the growing death toll of civilians. On Tuesday he said he was 鈥渙utraged and heartbroken鈥� over the latest aid worker deaths.

鈥淭his conflict has been one of the worst in recent memory in terms of how many aid workers have been killed,鈥� he said.

World Central Kitchen founder Jos茅 Andr茅s has a friendship with the Bidens and cooked meals at the White House when president Barack Obama was in office.

Andr茅s rejects Israel鈥檚 assertion that it was an accidental attack, saying the charity had clear communication with Israel about when and where the aid workers would be moving.

He said Israel鈥檚 right to defend itself does not extend to killing innocent people.

Jonathan Duguay, a close friend of Flickinger who was working in Cyprus for World Central Kitchen at the time of the attack, told The Canadian Press in an interview that Flickinger wasn鈥檛 afraid because the aid deliveries were co-ordinated with Israel鈥檚 assistance.

鈥淲e had an agreement with the IDF,鈥� said Duguay. 鈥淭here was a special route. They knew where we were.鈥�

Herzi Halevi, the Israel Defence Force chief of staff, said Wednesday he had received a preliminary report on the strike and insisted the aid workers were not intentionally targeted.

鈥淚 want to be very clear 鈥� the strike was not carried out with the intention of harming WCK aid workers. It was a mistake that followed a misidentification 鈥� at night during a war in very complex conditions. It shouldn鈥檛 have happened.鈥�

Halevi said World Central Kitchen does important work in difficult conditions and said Israel is 鈥渢aking immediate actions to ensure that more is done to protect humanitarian aid workers.鈥�

鈥淭his incident was a grave mistake,鈥� Halevi told reporters in a televised address in Israel.

鈥淚srael is at war with Hamas, not with the people of Gaza. We are sorry for the unintentional harm to the members of WCK. We share in the grief of their families, as well as the entire World Central Kitchen organization, from the bottom of our hearts.鈥�

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