AFP - Three Hamas members and a Palestinian policeman were killed on Thursday in a gunbattle in the northern West Bank in the second such incident in less than a week, an official said.
The shoot-out erupted in the northern town of Qalqiliya between the members of the Palestinian police and Hamas militants who had holed up in a house, an official with the security services said.
The house belongs to a Hamas member held in detention by the Palestinian Authority and those who were said to be inside included Mohammed Ateyeh of Hamas's armed wing, though it was unclear whether he had been killed.
On Sunday, three Palestinian policemen, Mohammed al-Samman, the leader of Hamas's armed wing in the northern West Bank and another militant, along with a passer-by were wounded during a similar clash in Qalqiliya.
Hamas warned at the time that the incident was a "red line" and that it held Palestinian president Mahmud Abbas and his forces wholly responsible.
Deep-seated rivalries between Hamas and Fatah boiled over in June 2007 when the Islamists violently seized control of the Gaza Strip, causing a split in Palestinian ranks that has become a key stumbling block in efforts to reach Middle East peace.
Security services in the West Bank are dominated by Fatah, the party of president Abbas which was ousted from Gaza in the Hamas takeover.
Abbas's power base has been limited to the occupied West Bank since Hamas ousted his Fatah party from the Gaza Strip, which remains under a crippling Israeli blockade.
The rival factions held five rounds of talks under Egyptian mediation in an attempt to reconcile but to no avail, and each side frequently accuses the other of launching campaigns of persecution.
Palestinians are pessimistic about the two sides reconciling. Some 51 percent believe that unity between Gaza and the West Bank will happen only after a long time while 27 percent say the split is permanent, according to a poll released on Sunday by the Palestinian Centre for Policy and Survey Research (PSR).
Rights group Amnesty International has lambasted both Hamas and Fatah for arbitrary detentions, torture and suppression of freedom of speech in their respective areas of control.
On May 20 the Western-backed Abbas swore in a new Palestinian cabinet that includes members of Fatah but not Hamas, further widening the sectarian rift.