Islamic Hamas movement on Wednesday urged its West Bank-based fighters not to surrender to security forces of Palestinian President Mahmoud Abbas. 'Our holy fighters will resist the detention attempts by the outlaw and unfaithful apparatuses,' said Abu Obaida, spokesman for Hamas military wing, in a statement sent to the media. Abu Obaida called on Ezz el-Deen al-Qassam Brigades' members to deal with pro- Abbas forces in the same way they deal with the Israeli army when trying to arrest them. According to the spokesman, the Palestinian National Authority' s (PNA) troops stepped up detention raids against Hamas members in the West Bank where Abbas' Fatah party holds sway. On Sunday, two Hamas militants and three policemen were killed in clashes in the West Bank city of Qalqilya. Hamas said the security forces started the shooting when they chased down the two gunmen who holed up in a building. The recent clashes and Abu Obaida's call fuel tension between Hamas, which controls the Gaza Strip, and Fatah. 