Residents of Nur Shams camp in the occupied West Bank are fearful for their future after an Israeli raid this week damaged the UN agency for Palestinian refugees office there.

The 13,000 inhabitants of the camp near the northern city of Tulkarem depend heavily on the United Nations Relief and Works Agency for Palestine Refugees.

UNRWA notably runs two schools, a clinic and sanitation services in Nur Shams.

Stunned refugees watched as workers cleared rubble from around the office, which was almost totally destroyed in an "anti-terrorist" operation on Thursday.

"For us, it's UNRWA or nothing," Shafiq Ahmad Jad, who runs a phone shop in the camp, told AFP.

"For the refugees... they look to UNRWA as their mother," said Hanadi Jabr Abu Taqa, an agency official in charge of the northern West Bank.

"So imagine if they lost their mother."

UNRWA chief Philippe Lazzarini blamed the destruction on Israeli forces, saying they had "severely damaged" the office.

But the military firmly denied the accusations, telling AFP that the damage was "likely" caused by explosives planted by "terrorists".

The office will have to be relocated, "a significant investment" according to Roland Friedrich, the agency's head in the West Bank.

"The psychological impact, of course, is devastating," he added after speaking to residents on Saturday.