"The world is watching, day after day, horrifying scenes of Palestinians being shot, wounded or killed in Gaza while simply trying to eat," UN relief chief Tom Fletcher said.

UNITED NATIONS, June 4 (Xinhua) -- UN humanitarians said Wednesday that less than half of their aid trucks submitted for Israeli clearance were allowed into Gaza, while the new, deadly U.S.-run aid process suspended operation.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said only 50 flour-bearing trucks of the more than 130 aid trucks submitted for final clearance at the only crossing, Kerem Shalom/Karem Abu Salem, were approved for entry into Gaza on Wednesday.

It was announced earlier in the week that the U.S.-run, Israeli-approved Gaza Humanitarian Foundation (GHF) aid setup that has led to scores of deaths and injuries from Palestinians rushing to its aid distribution points was suspending its operation for Wednesday to assess the plan.

The United Nations and several international aid agencies were critical of the GHF operation from the day the new scheme was announced, saying they had the track-proven system, despite Israeli claims Hamas was appropriating aid for its means.

UN relief chief Tom Fletcher said in a statement on Wednesday that the GHF operation is the outcome of a series of deliberate choices that have systematically deprived 2 million people of the essentials they need to survive.

"The world is watching, day after day, horrifying scenes of Palestinians being shot, wounded or killed in Gaza while simply trying to eat," he said. "These are not isolated incidents, and the perpetrators must be held accountable."

The under-secretary-general for humanitarian affairs said that emergency medical teams in Gaza confirmed treating hundreds of trauma cases since the new aid scheme began. He echoed the call of UN Secretary-General Antonio Guterres for immediate, independent investigations.

"No one should have to risk their life to feed their children," Fletcher said. "We must be allowed to do our jobs: We have the teams, the plan, the supplies and the experience. Open the crossings, all of them. Let in lifesaving aid at scale from all directions. Lift the restrictions on what and how much aid we can bring in. Ensure our convoys aren't held up by delays and denials."

OCHA said that since the Kerem Shalom/Karem Abu Salem crossing reopened nearly a month ago, the world body and its partners collected fewer than 400 of the thousand-plus truckloads submitted for Israeli final clearance.

"Let's be clear," said Stephane Dujarric, chief spokesman for Guterres, on the limited UN aid being allowed into Gaza. "The Israeli authorities are facilitating one distribution channel and hampering another."

OCHA said humanitarian teams work hard to collect supplies from Kerem Shalom/Karem Abu Salem and bring them closer to where people need them inside Gaza. But the attempts face significant hurdles. One attempt on Tuesday was denied access altogether, and another managed to retrieve just over a dozen truckloads carrying flour.

"That denied attempt to access Kerem Shalom was one of six access denials humanitarian teams faced (on Tuesday) across the Gaza Strip, out of a total 13 attempts," the office said. "Such denials prevented these teams from carrying out interventions as critical as trucking water."

OCHA said another denied attempt was to retrieve urgently needed fuel. Partners have rationed the supplies. But without immediate access to fuel that is already inside Gaza but located in hard-to-reach areas that are either militarized or subject to displacement orders, more critical services will have to suspend operations soon.

Additionally, the humanitarians said the relentless hostilities in Gaza cause more deaths, displacement and damage to essential infrastructure.

OCHA said the latest displacement figures show that in the past three weeks, more than 100,000 Gazans were forced to flee in northern governorates.

"Partners working in health warn that facilities are being heavily impacted by the ongoing hostilities," the office said. "More and more medical facilities are suspending their operations. On Monday, the remaining staff and patients in the Indonesian Hospital in North Gaza were evacuated. As a result, not a single hospital remains functional in North Gaza."

UN Deputy Humanitarian Coordinator Suzanna Tkalec visited Gaza City's Al Ahli hospital, which has sustained multiple attacks since the beginning of the war and was told that preventable deaths are occurring due to shortages of critical supplies, including antibiotics.

Tkalec called for the protection of health facilities and support for the United Nations and its partners to deliver aid on a large scale to alleviate people's suffering. The world body and its partners are continuously appealing to the Israeli authorities to enable humanitarians to address the crisis in Gaza meaningfully.