Israeli troops killed at least 79 Palestinians in the northern Gaza Strip on Sunday, local health authorities said, after large and desperate crowds mobbed one of the U.N. convoys carrying a trickle of aid into the mostly besieged enclave.

The U.N. World Food Program said its 25-truck convoy was mobbed shortly after it passed through the Zikim border crossing from Israel into Gaza. “Our convoy encountered massive crowds of hungry civilians which came under gunfire,” the agency said in a statement.