Hamas threatened on Thursday to escalate its "resistance" attacks against Israel in response to the arrest of dozens of its representatives in the West Bank by the IDF. The movement also rejected an appeal by Palestinian Authority Chairman Mahmoud Abbas to stop firing Kassam rockets at Israel. Abbas, who met in Gaza City Thursday with EU Foreign Policy Chief Javier Solana, called for an end to the rocket attacks on Israel. "These homemade rockets are useless, and we don't need them in order to reach a truce in the Gaza Strip, and then in the West Bank," he said. The arrest of more than 30 Hamas leaders is seen as a severe blow to the movement because it leaves the group without a political leadership in the West Bank. Two of Hamas's most prominent figures in the West Bank, Education Minister Nasser Eddin Shaer and legislator Sheikh Hamed Bitawi, a spiritual leader of Hamas, were among those snatched from their homes in a pre-dawn operation launched by the IDF in West Bank cities that included Kalkilya, Nablus, El-Bireh and Bidya. The mayors of all four cities were arrested. The army also shut down 10 Hamas offices in the West Bank, including in Jenin, Ramallah, Nablus and Bethlehem. According to security officials, the arrests were intended to put additional pressure on Hamas and send a clear message that Israel would target all of the movement's officials until the Kassam rocket attacks on southern Israel ceased. By late Thursday evening, 10 rockets had been fired at Israel. One landed in Sderot and caused damage to a number of parked cars. Security officials said that the Shin Bet (Israel Security Agency) planned to file indictments against the arrested Hamas officials, who, they said, were involved in funding terror activity and transferring terror know-how from the Gaza Strip to operatives in the West Bank. Defense Minister Amir Peretz said the arrests were part of Israel's attempt to neutralize Hamas. "Arrests are better than shooting," he told Army Radio. "The arrest of these Hamas leaders sends a message to the military organizations that we demand that this firing [of rockets] stop." Also Thursday, the IDF continued to strike terror targets in the Gaza Strip and bombed a Hamas outpost in northern Gaza. Hamas reported one of its bases in Gaza City was attacked, but said there were no Hamas casualties. Rescue workers said four civilians were lightly injured by flying glass and debris. A few minutes later, Palestinian security said IAF aircraft hit another Hamas base in central Gaza, near the town of Deir el-Balah. No one was hurt, they said. The military said it had targeted Hamas infrastructure. Hamas leaders strongly condemned the crackdown, hinting that the arrests could be part of an Israeli scheme to help Abbas's Fatah faction in the ongoing power struggle with Hamas. "These arrests are aimed at destroying the Palestinian political reality," said PA Prime Minister Ismail Haniyeh. Addressing supporters in Nablus, whose mayor, Adli Yaish, was among those arrested by the IDF, a defiant Haniyeh declared: "These arrests prove that Hamas is moving in the right direction and that it has not compromised its principles. The detention campaign will fail in breaking the will of the Palestinians and we will emerge even stronger than before." Hamas legislator Salah Bardaweel warned in a phone interview that targeting Hamas leaders, activists and institutions would eventually bring about the collapse of the Palestinian Authority. Asked to comment on statements by Israeli security officials to the effect that the arrests were designed to send a message to Hamas that it must stop firing rockets at Israel, Bardaweel said: "The opposite is going to happen. By targeting Hamas, Israel is destroying the Palestinian Authority, which is needed for stability in the region." Another Hamas official, Ghazi Hamad, condemned the arrests as "brutal" and warned that the Israeli crackdown would lead to another cycle of violence in the region. "Israel will bear the consequences of its irresponsible actions," he cautioned. PA Information Minister Mustafa Barghouti (independent) claimed that Israel was seeking to reoccupy the Palestinian territories, eliminate the Palestinian Authority and rescind all agreements that were signed with the Palestinians.