Scores of Fatah policemen who used to serve in the Palestinian Authority security forces in the Gaza Strip have now joined the al-Qaida-affiliated group calling itself the Army of Islam, sources in the Hamas-controlled Interior Ministry told The Jerusalem Post Thursday. Meanwhile, Fatah's armed wing, the Aksa Martyrs Brigades, claimed responsibility for firing 20 rockets from the Gaza Strip recently. The group said the attacks signaled the beginning of a military campaign dubbed "Operation Gaza Autumn," in the course of which it would fire hundreds of rockets at Israeli communities. It said residents of Sderot had two choices: leave or die. Fatah officials in Ramallah said they did not know if the threat by the Aksa Martyrs Brigades was genuine. "We don't know what's happening in the Gaza Strip," a senior Fatah official said. "Ever since the Hamas coup last June, we have no idea what's happening on the ground." The official, however, did not rule out the possibility that disgruntled Fatah activists were behind the recent spate of rocket attacks, or that some former Fatah-affiliated policemen had joined the Army of Islam. According to the sources Hamas's Interior Ministry, dozens of Fatah-affiliated policemen who recently lost their jobs have joined the al-Qaida-linked group. The Army of Islam is headed by Abu Muhammad al-Ansari, who is also known as Mumtaz Dughmush. Ansari is a former PA Preventive Security Service officer in the Gaza Strip. He belongs to the Dughmush clan, whose members have kidnapped several foreign nationals, including BBC reporter Alan Johnston, and bombed Internet cafes, hair salons and restaurants. The Army of Islam, which is described by some Palestinian security officials as al-Qaida's branch in Palestine, was one of three groups that participated in the kidnapping of IDF soldier Gilad Schalit in June 2006. The other two groups were Hamas and the Popular Resistance Committees. But Hamas has since distanced itself from the Army of Islam, whose members have been kept away from Schalit. It did so after suspicions were aroused in Hamas that Ansari had received money from Fatah security officials to reveal the whereabouts of the soldier. Tensions between Hamas and the Army of Islam reached a boiling point immediately after Hamas took over the Gaza Strip. The Army of Islam initially refused to release Johnston, but later did so after its leaders struck a deal with Hamas. According to the agreement, the group was permitted to retain its weapons on condition they only be used to attack Israel. Over the past few months, the Army of Islam has been involved in the smuggling of large amounts of weapons and explosives into the Gaza Strip from Sinai, according to PA security officials. They told the Post members of the group had established close ties with al-Qaida operatives in Egypt and other Arab and Islamic countries. Last week, Egyptian security forces captured two members of the Army of Islam as they were trying to smuggle weapons into the Gaza Strip. A top Hamas official in Gaza City described Ansari as a "deranged and illiterate" man who was obsessed with [Jordanian arch-terrorist] Abu Musab Zarqawi, the slain leader of al-Qaida in Iraq. "This man can't even read or write," he said. "But he's dangerous." The official confirmed that the Army of Islam had recruited scores of Fatah policemen. He said documents seized by Hamas showed that Ansari and his men were on the payroll of one of the PA security forces and that they had been receiving monthly payments of $27,000. "They will take money from anyone, even from people they consider infidels and apostates," the Hamas official said.