The UN relief agency for Palestinian refugees has denied Israel's claim that it has detained 13 of its staff in Gaza on suspicion of links to terrorism.
Rocket or stretcher? Israel does not seem so sure any more
Spokesman Paul McCann accused Israel of deliberately muddying the waters after retracting an accusation that a UN ambulance was used by militants.
He said a member of the Gaza staff had been in detention for two years, but knew of no-one else in Israeli custody.
Israeli General Yisrael Ziv first referred to the detentions on Tuesday.
"We have in our hands a list of 13 detainees who are to be indicted, they are UN people with suspected links to terrorism," the general told a news conference.
Army spokesman Capt Jacob Dalal later said the words had been taken out of context and detentions had in fact occurred during the last four years.
Some of the 13 detainees may not actually be in custody now, Capt Dalal said.
"It seems to be part of a background of false allegations made against us in order to muddy the waters," Mr McCann told BBC Radio 4's Today Programme.
The United Nations Relief and Works Agency (Unrwa) says 24 of its Palestinian staff have been detained in the West Bank, but says Israel has repeatedly failed to explain why they were being held.
A UN team sent by Secretary General Kofi Annan has arrived in Israel to examine what the authorities there say is evidence that Unrwa staff are linked to terrorist organisations.
Mr McCann pointed out that Gen Ziv's news conference was "actually held so the Israeli military could admit that they were not sure" about an earlier claim to have video footage of a rocket
loaded onto a UN ambulance in Gaza.
"They effectively backed down and accepted our claim that it was a stretcher," Mr McCann said.
When he was asked about whether the object filmed was a rocket or a stretcher, Gen Ziv said: "I suggest we don't deal with the object but rather with the context."
Peter Hansen has been the focus of Israeli ire before
He said that, regardless of what the filmed object actually was, UN employees "are exploiting the organisation's vehicles in order to support terror-related activities."
Unrwa has strenuously denied the charge.
"We insist people follow the rules and the regulations of impartial United Nations civil servants and the vast majority of them are extremely proud to be UN staff working on behalf of their community," Paul McCann told Today.
The controversy follows closely on the heels of a storm over Unrwa chief Peter Hansen's admission that some of his staff may by members of the Islamic Resistance Movement, better known as Hamas.
Mr McCann told Today: "We cannot police people's sympathies but we can police their behaviour and activities."
Unrwa was formed to relief the Palestinian refugee crisis that followed the establishment of Israel in 1948.
It currently provides regular food aid to about 1.5m Palestinians in the West Bank and Gaza Strip. It also runs schools and clinics, and provides shelter for thousands of Palestinians made homeless by Israel's house demolition policy.