Of 164 charitable institutions that the movement ran in the West Bank, 138 have been closed completely in the past three years, according to Mr Ramahi. The rest had been allowed to continue only after their executive boards were replaced. Mr Ramahi said the institutions had been targeted because they provided a “link between Hamas and the people”.

He denied that charities had funnelled money to Hamas, and pointed out that after the September 11 attacks, regulations for charities had been tightened to such a degree that even if people wanted to launder money through charities, “there was no way to do so”.

Nevertheless, it is clear that the focus on charitable societies forms part of a larger financial security strategy that one Palestinian intelligence source said was a “carefully planned, front line” effort to impose control over the flows of money into the West Bank.

This effort has included tighter controls over money exchange shops and greater oversight of bank accounts. Charities had been one way to launder money from abroad, the intelligence officer said, citing an example from Hebron where one charity had 52 security guards on its payroll. “These turned out to be salaries for Izzedine al Qassam members [the armed wing of Hamas],” said the source, who declined to be identified but who is intimately familiar with the financial investigations of the Palestinian security services.

Officially, the PA maintains that the charities were closed because of financial irregularities. But while the intelligence source maintained that the charities had been a way for Hamas to bring in money, he said they were not necessarily the most effective way. He also conceded that many of the accused charities had yet to have their cases heard before the courts.

The focus on Hamas and its institutions, he added, had been a political decision. “There was a strong feeling that if Hamas was not targeted, what happened in Gaza could be repeated here.”

Palestinian security sources maintain that Hamas has been debilitated by the crackdown. One claimed that the PA has confiscated as much as US$100 million (Dh367m) in cash from the movement and its institutions. Hamas security sources say that the number is closer to $20m and that the money belongs to families of prisoners and those orphaned in fighting with Israel.

Mr Ramahi, meanwhile, rejected that Hamas had been weakened in the West Bank. On the contrary, he said, the closure of charitable institutions was backfiring on the PA.

“These charities looked after 100,000 people. Their closure is an injustice, and for this, people will react.”