Gaza's Hamas government has launched a month-long campaign urging alleged Palestinian "collaborators" with Israel to turn themselves in return for leniency.

"We announce the opening of the door to repentance for remaining collaborators and for all those who have fallen into the traps set by the enemy's intelligence services," interior ministry spokesman Islam Shahwan told reporters on Tuesday.

"We urge them to return to the bosom of their people and their families," he said, noting that the offer of clemency was open until April 11.

Under Palestinian law, collaboration with Israel is punishable by death.

All execution orders must be approved by the Palestinian president before they can be carried out, but Hamas no longer recognises the legitimacy of incumbent Mahmoud Abbas, whose four-year term ended in 2009.

Following a deadly eight-day confrontation with Israel in November, the Hamas government announced the creation of a committee to examine the "unlawful executions" of Palestinians accused of spying for Israel during the conflict.

In at least two incidents during Israel's bombardment of the territory, seven people were gunned down after being accused of being collaborators.

The bodies of six of them were dragged behind vehicles through the streets of Gaza City.

The killings were claimed by Hamas fighters from the Ezzedine al-Qassam Brigades and notes were pinned to the bodies reading: "Al-Qassam Brigades announces the execution of the traitors."

'A message to Israel'

At the time, Hamas deputy politburo chief Moussa Abu Marzouq denounced the killings on his Facebook page branding them as "totally unacceptable."

"Punishment is only permissible within the framework of the law," he wrote.

But Mahmud Zahar, a Gaza-based senior Hamas leader endorsed the killings.

"Human rights are for honourable citizens, not for collaborators who cause sorrow," he said at the time, referring to people killed by Israel as a result of information passed on by informants.

The UN High Commissioner for Human Rights condemned the "summary executions" and said the victims had previously been in Hamas government custody.

Shahwan did not elaborate on the punishment a repentant "collaborator" could expect, but said he expected the offer to evaporate Israel's pool of informants in the territory.

"This campaign is a message we send to the Zionist enemy to assert the failure of its security and intelligence programme," he said.

"Sources of information about our people and our resistance in this manner will soon dry up."

Mohammed Lafi, an official with Gaza's internal security services told reporters that one of Israel's recruitment methods was to "blackmail" Gazans crossing for hospital treatment in Israel or the occupied West Bank.

Source: Agencies