The Israeli army on Friday admitted a series of errors and violations of its rules in the killing of seven aid workers in Gaza, saying it had mistakenly believed it was "targeting armed Hamas operatives".

The two brigade officers who ordered the drone strikes, a colonel and a major, are being fired, the army said, and its Southern Command chief reprimanded.

It was a rare confession of wrongdoing by Israel in its nearly six-month war against Hamas militants in the Gaza Strip, where the health ministry of the Hamas-ruled territory says more than 33,000 people, mostly civilians have been killed.

The victims -- an Australian, three Britons, a North American, a Palestinian, and a Pole -- were killed Monday night in three air strikes over four minutes by an Israeli drone as they ran for their lives between their three vehicles, the military said.

The US-based charity for which they worked, World Central Kitchen, demanded an independent inquiry, and Poland called for a "criminal" probe after the military's announcement.

The drone team who killed the aid workers made an "operational misjudgment of the situation" after spotting a suspected Hamas gunman shooting from the top of one of the aid trucks the aid workers were escorting, an internal Israeli military inquiry found.

Senior Israeli officers showed reporters clips from drone footage of what they said was a "Hamas operative" joining the US-based World Central Kitchen (WCK) convoy.

Although the roofs of the three aid workers' vehicles were emblazoned with large WCK logos, retired Israeli general Yoav Har-Even, who is leading the investigation, said the drone's camera could not see them in the dark.

"This was a key factor in the chain of events," he said.

The aid group has said its team was traveling in a "de-conflicted" area in a convoy of "two armored cars branded with the WCK logo and a soft skin vehicle" at the time of the strike.

"Despite coordinating movements with the (Israeli army), the convoy was hit as it was leaving the Deir al-Balah warehouse," WCK said.

The army said aid was moved at night to avoid deadly stampedes by hungry Gazans.

The aid workers' deaths "outraged" US President Joe Biden who demanded Israeli Prime Minister Benjamin Netanyahu order steps toward an "immediate ceasefire" in a telephone call Thursday.

Israel later said it would allow "temporary" aid deliveries into northern Gaza, where the United Nations has warned of imminent famine.

Har-Even admitted that "the three air strikes violated standard operating procedures".

 'State of mind' 

But he argued that "the state of mind" of the Israeli drone commanders "was that they were striking cars that had been seized by Hamas" after they thought one passenger was carrying a gun rather than a bag.

The aid workers were killed after they had overseen the unloading of a ship carrying 300 tonnes of food aid from Cyprus to a warehouse inland.

But as they drove south at 11:09 pm on April 1 the drone "struck one car, and identified people running out of the car and entering the second car," said Har-Even.

"They decided to hit it, which was against standard operating procedures. Then they struck the third car."

Asked by AFP, the general was not able to explain what happened to the "Hamas gunman" on the truck but he conceded that they had been mistaken to think armed Hamas suspects had joined the WCK aid workers in the three pickups.

"It is a tragedy. It is a serious mistake that we are responsible for," Israeli military spokesman Daniel Hagari told reporters. "A mega event... that shouldn't have happened. We will make sure it won't happen again."

Har-Even said it was a breakdown in communication and coordination about the convoy in the chain of military command which may have led to the strikes.

 'Biggest mistake' 

 He said that WCK had provided all the information necessary, but it was not passed down.

"The biggest mistake was that (the drone team) didn't have the coordination plan," he said. "Their belief was the vehicles were Hamas based on operational misjudgment and misclassification."

Har-Even briefed WCK founder Jose Andres, a Spanish-born celebrity chef, Friday before information on the circumstances of the strikes was released. Andres called the attack a "targeted Israeli strike" on his staff.

The bloodiest ever Gaza war erupted with Hamas's unprecedented October 7 attack which resulted in the deaths of 1,170 Israelis and foreigners, most of them civilians, according to an AFP tally of official Israeli figures.

Israel's retaliatory campaign, aimed at destroying Hamas, has killed at least 33,091 people, mostly women and children, according to the Gaza health ministry.

Christopher Lockyear, secretary general of Doctors Without Borders (MSF), said on Thursday that a total of nearly 200 humanitarians have been killed during the Gaza war.