Defying a Palestinian Authority ban on public displays of weapons, about 1,000 people brandishing assault rifles and rocket launchers marched through Gaza City on Thursday and vowed to hold on to their arms. Members of the Al Aksa Martyrs' Brigades, fired into the air while their leaders made speeches insisting on the right to bear arms against Israel. "Brothers, don't ever give up your weapons," said a senior Gaza leader known by the nickname Abu Ibrahim. "We can't lay down our arms while Israel still occupies the West Bank, surrounds Gaza and controls our airspace and coastal waters, which means that the occupation remains and resistance will continue." The arms ban officially went into effect two months ago days after an explosion at a rally for Hamas killed 25 people. Hamas blamed Israel, but Palestinian investigators said the blast was set off when militants mishandled explosives they were displaying at the rally. Al Aksa spokesman Zakariye Assouli said the group supported the Palestinian Authority's efforts to stop internal violence while reserving the right to avenge Israeli attacks. "We respect our brothers in the political leadership," Assouli said. "We honor their commitments, but they can't ask us to watch daily Israeli aggression and to remain silent." The Palestinian Authority has had great difficulty trying to impose order in Gaza, where terrorists routinely flaunt their power.