While Egypt is making efforts to stop the smuggling of arms into the Gaza Strip, at least one ton of explosives is being conveyed across the Sinai border Gaza each month, a high-ranking IDF officer revealed on Thursday. Following Israel's withdrawal from Gaza last year, Egypt deployed 750 border policemen along the border with Gaza in agreement with Israel. The force, the officer said, has proven to be "ineffective" in stopping the smuggling into Gaza despite the Egyptian government's interest and readiness to assist Israel in preventing the terror buildup in the Palestinian territory. Besides being a breeding ground for Islamic extremists, the Sinai desert was also a main conduit for high-grade explosives, grenades and anti-tank missiles that were being transferred into Gaza, the officer revealed. The source of the weaponry, the officer said, was from various countries, including Iran and Egypt's southern neighbor Sudan. "The smuggling must be thwarted before it reaches Sinai," the officer said. "There are loads of explosives in the desert. Some is transferred to Gaza and some is used for the attacks against targets in the Sinai." The officer further revealed that Palestinian terrorists have traveled to Iran for terror training following which they returned to the Gaza Strip. Palestinian terror groups in Gaza, he said, were also trying to import and in some cases manufacture advanced homemade anti-aircraft and anti-tank missiles. He said Hizbullah had representatives stationed in the Gaza Strip. "They want to import or develop on their own new weapons that they don't have," the officer said. "Our job is to try to stop them from succeeding." Meanwhile Thursday, the Shin Bet (Israel Security Agency) revealed for publication that in a joint operation with the IDF last month it arrested an operative of the Palestinian Popular Resistance Committees in Gaza who revealed the location of a terror tunnel being dug under the Karni cargo crossing into Gaza. Majad Kambaz, 29, of Gaza was arrested last month for alleged involvement in terror activity against Israel. Kambaz revealed to his interrogators the exact location of the tunnel that was being dug under the security fence and the Karni crossing. The terrorists planned to plant a large amount of explosives inside the tunnel and under the offices of the Israeli administration station at Karni that is in charge of the transfer of goods to the Palestinian population in Gaza.