The United Nations is frantically searching for a large stockpile of unexploded weapons that have disappeared in the Gaza Strip, the BBC reported.

The explosives, fired by Israel during the recent Gaza offensive, including aircraft bombs and white phosphorus shells, were being guarded by Hamas and were scheduled to be safely disposed of by the U.N.

Israel has accused Hamas of taking the weapons and the U.N. has called for their immediate return.

"We are anxious to get the return of this ordnance. It's clearly extremely dangerous and needs to be disposed of in a safe manner," Richard Miron, the senior U.N. spokesman in Jerusalem, told the BBC. "This is our primary concern."

A U.N. Mines Action Team found the explosives in a storage site in Gaza City on Feb. 2. They included three 2,000-pound bombs and eight 500-pound bombs that had been dropped by Israel but failed to explode, the BBC reported.

When U.N. officials returned to the warehouse Sunday to retrieve the weapons, which was under a Hamas police guard, the explosives were gone.

Israeli military spokesman Peter Lerner told the BBC they had been "commandeered by Hamas."

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