Israeli soldiers opened fire on Tuesday morning near crowds of Palestinians walking toward a new food distribution site in southern Gaza, the Israeli military said.

The Gaza health ministry said that the troops killed at least 27 people and wounded dozens.

The military said the troops fired near “a few” people who had strayed from the designated route to the site and who did not respond to warning shots. The statement called them “suspects” and said they had “posed a threat” to soldiers, but a military spokeswoman declined to explain the nature of the perceived threat. It added that was “aware of reports regarding casualties, and the details of the incident are being looked into.”

The shootings, which the military said occurred roughly half a kilometer, or some 550 yards, from the food distribution site, were the latest turmoil surrounding a contentious new Israeli-backed system for food distribution in Gaza.

Israeli soldiers also opened fire on Sunday near an approach to the same food distribution site, in an incident that Palestinian officials said killed at least 23 people. It followed several episodes of unrest last week.

Much is riding on the fate of the new aid system. Aid agencies say Gaza faces widespread starvation following an 80-day Israeli blockade on food deliveries between March and May.

The new aid program is overseen by a new and untested private aid group, Gaza Humanitarian Foundation, which pays American contractors to distribute food from a handful of sites that are mostly in Israeli-occupied areas of southern Gaza. It replaced a system overseen by the United Nations, which distributed food from roughly 400 sites across the entire territory.