The IDF needs to change the way it is fighting against the Kassam rocket attacks from Gaza, because the current modus operandi is not working, Public Security Minister Avi Dichter said at Sunday's cabinet meeting. Ditcher's comments came after Shin Bet (Israel Security Agency) head Yuval Diskin said approximately 1,000 terrorists were killed in the Gaza Strip over the last two years. Dichter, who was the Shin Bet head just prior to Diskin, said that although a significant achievement, this represented just 5 percent of the 20,000 terrorists believed to be in Gaza, and that Israel had not succeeded in stopping the "war of attrition" that was taking place there. Diskin said that while Israel was hitting at the terrorists, the Palestinians were attacking civilians, in what was an example of asymmetrical warfare; he called on the government to dramatically "change the mode of operation" to put an end to the war of attrition. The rockets had driven 3,000 Sderot residents from their homes, Dichter said. He said Israel needed to create a level of deterrence that would keep Hamas from firing at Israel. In the past, Dichter has called for the creation of a "buffer zone" in Gaza to distance the Kassam rockets from Israeli communities, and to patrol the buffer zone from the air. On Sunday, Gazans fired eight mortar shells at the Western Negev. One lightly damaged a home in Kibbutz Netiv Ha'asara, without causing casualties. Two shells struck in area of the kibbutz, and the six fell near the Erez crossing to the northern Gaza Strip. Jerusalem Post staff contributed to this report.