The U.S.-backed Gaza Humanitarian Foundation will not give out any aid on Wednesday as it presses Israel to boost civilian safety beyond the perimeter of its distribution sites, a day after dozens of Palestinians seeking aid were killed.

A new program for getting desperately needed food into the hands of starving Palestinians in Gaza is only days old, but it’s already mired in chaos and tragedy.

The Palestinians were shot and scores wounded as huge crowds assembled to try and get food from a new aid distribution center. An Israeli military official said soldiers fired warning shots.