Six young Palestinians were caught by the IDF after they tried crossing into Israel from Gaza on Sunday, a day after two gunmen scaled the Strip's security fence and amid calls by residents of nearby communities to beef up security. On Saturday, two terrorists were killed by IDF troops after they used a sophisticated rope to climb over a concrete wall into Israel from northern Gaza and opened fire at a guard stationed at the entrance to the Gaza Liaison Administration near the Erez crossing. On Sunday afternoon, six unarmed youths, who officers said were most probably sent to check the IDF's level of alertness, were caught nearby trying to cross the fence. Defense officials said the IDF would continue to maintain a high level of readiness along the security fence in an effort to curb the recent rise in the number of Palestinians trying to infiltrate into Israel. Since the beginning of the month, around 20 Palestinians, most of them searching for work, have been caught. Also on Sunday, the IDF bombed unmanned Kassam rocket launchers in the northern Gaza Strip. No one was injured in the strike. Officers in the Southern Command said military forces were properly deployed along the Gaza perimeter but that it was possible the Defense Ministry would decide to allocate funds for additional technological means that could be used to detect Palestinian infiltrations. Gil Nir, head of Moshav Netiv Ha'asara's rapid-deployment security team, told The Jerusalem Post that such devices, including sensors, needed to be installed on and along the Gaza security fence. Most of the border is closed off by an electronic fence that if touched sets off an alarm inside an IDF control room. The 2.5-kilometer long concrete wall scaled by terrorists on Saturday does not have any electronic sensors. "This is a question of funding and the defense establishment needs to find the money so they can install the sensors as well as other technological systems," Nir said, adding that it was quite clear that the terrorists knew that the concrete wall they were climbing was without sensors. "This is a serious issue and we cannot just wait for blood to be spilled before we act." IDF sources said the military was using all of the means at its disposal to prevent infiltrations. In the past two months, the IDF has killed more than 65 terrorists in operations inside Gaza and along the perimeter. Deputy Defense Minister Matan Vilna'i said there was no proof that the wall did not provide adequate protection, adding that no defense system could prevent all infiltrations. "The IDF acted exceptionally," he said. "The bottom line is, two terrorists were killed in the incident. We have here a military system unparalleled in its efficiency." Meanwhile Sunday, the IDF allowed 75 Palestinians to leave the Gaza Strip and travel abroad. More than 4,000 Palestinians with overseas work and study permits have been living in fear of losing badly needed jobs and academic credits after Israel and Egypt clamped a closure on Gaza following the terror group's takeover. Several hundred foreign nationals and Palestinians with dual citizenship, as well as a few Palestinians working and studying abroad, had already been permitted to cross through Israeli territory en route to other points. But Sunday's departure from Gaza was the first by a large group of Palestinians with foreign permits. They passed through the Erez crossing into Israel after lengthy security checks, then were bused to a southern Israel border crossing with Egypt 140 kilometers away. Defense officials said that Sunday's transfer was a pilot test run and if it will continue to go smoothly could serve as a temporary solution for Palestinian humanitarian cases. AP contributed to this report.