Chaos erupted on the second day of aid operations by a new US-backed group in Gaza as desperate Palestinians overwhelmed a centre distributing food on Tuesday, breaking through fences.

Israel said nearby troops fired warning shots.

An AP journalist heard Israeli tank and gunfire and saw a military helicopter firing flares.

The Israeli military said its troops fired the warning shots in the area outside the centre and that “control over the situation was established.”

At least three injured Palestinians were seen by the Associated Press being brought from the scene, one of them bleeding from his leg.

The distribution hub outside Gaza’s southernmost city of Rafah had been opened the day before by the Gaza Humanitarian Foundation, which has been slated by Israel to take over aid operations despite opposition from the United Nations and other humanitarian organisations.

Palestinians have become desperate for food after nearly three months of Israeli blockade pushed Gaza to the brink of famine.

On Tuesday, hundreds of thousands of men, women and children walked for several miles from the sprawling tent camps along Gaza’s Mediterranean coast – through Israeli military lines – to reach the GHF hub.

Ahmed Abu Taha, who was among those seeking aid, said crowds of people stormed into the distribution centre, breaking fences.

He heard gunfire and saw Israeli military aircraft overhead.

“It was chaos,” he said. “People were panicked.”

Another Palestinian, Saleh Abu Najjar, said he heard a tank firing from a distance, east of the centre.

“The situation was very dangerous and people were frightened,” he said.

UN chief Antonio Guterres's spokesman said the scenes of thousands of people rushing the aid distribution site were "heartbreaking,"

"We have been watching the video coming out of Gaza around one of the distribution points set up by the Gaza Humanitarian Foundation. And frankly, these video, these images, are heartbreaking to say the least," Stephane Dujarric said.

"As the Secretary-General noted last week, we and our partners have a detailed, principled, operationally sound plan supported by Member States to get aid to [the] desperate population," he added. (Agencies)