Israel's U.N. ambassador demanded Sunday that the world body investigate the actions of its top official in Gaza (search) after Israeli accusations that Gaza militants used a U.N. vehicle to transport a homemade rocket.

Ambassador Dan Gillerman said he was asking U.N. Secretary-General Kofi Annan (search) to investigate Peter Hansen, head of the U.N. Relief and Works Agency, after the Israeli army released a video taken by an unmanned aircraft flying over the Jebaliya refugee camp. UNRWA assists Palestinian refugees in the West Bank and Gaza Strip.

The video was released while the army launched a wide-scale operation in Jebaliya and nearby towns in an attempt to halt Palestinian rocket attacks on towns in Israel. Those rocket attacks killed two Israeli preschoolers Wednesday.

Israel, which has long accused UNRWA (search) of bias, said the footage showed militants loading a rocket into a U.N. vehicle. The United Nations denied the accusation and said Sunday the footage showed a worker loading a stretcher into an ambulance.

"We will demand an inquiry committee with the authority to reach unequivocal conclusions — maybe even personal conclusions — especially regarding Peter Hansen, the UNRWA envoy in Israel, who for years has expressed anti-Israeli, biased, unrestrained positions and statements," Gillerman told Israel Radio.

Director of operations for UNRWA, Lionel Brisson, said U.N. workers do not carry weapons or armed militants in U.N. vehicles.

"We want an apology from the Israelis, because we didn't commit any wrongdoing," he said.