The director of the U.N. World Food Program says the program has “paused” its distribution of humanitarian aid from an American-built pier off Gaza out of concern for the safety of its workers.

WASHINGTON (AP) — The director of the U.N. World Food Program said Sunday the program has “paused” its distribution of humanitarian aid from an American-built pier off Gaza, saying she was “concerned about the safety of our people” after what had been one of the deadliest days of the war there.

Saturday saw both an Israeli military assault that freed four hostages but left 274 Palestinians and one Israeli commando dead, and, Cindy McCain said, two of WFP’s warehouses in Gaza had been “rocketed” and a staffer injured.

Sunday’s U.N. announcement of the pause appears the latest setback for the U.S. sea route, set up to try to bring more aid to Gaza’s starving people.