Since the IDF seized the Philadelphi Corridor—the strip of land between Gaza and Egypt—in May, it has uncovered at least 25 tunnels connecting the two territories, including one big enough to drive trucks through. These tunnels are thought to be the main corridor through which Hamas has imported arms and other military supplies. Lior Ben Ari explains that smuggling across this border has gone on since 1982, when Israel returned the Sinai Peninsula to Egypt. But the problem took on new dimensions in 2005, when Israel withdrew from Gaza:
Nearly twenty years ago, a conversation took place between the Egyptian president Hosni Mubarak and the Israeli defense minister Shaul Mofaz that outlined a plan for deploying 750 Egyptian police officers along the Philadelphi Corridor within months to prevent arms smuggling. . . . During the talks, Mubarak made it clear to Mofaz that he expected Israel to withdraw from the Gaza Strip, including the Philadelphi Corridor, and that Egypt would handle security issues in the area.
After the conversation, Mofaz noted that the Egyptian activity would also address intelligence against smugglers, their arrests, and operations within Sinai, not just at the border. Even then, Egypt refused any Israeli presence along the narrow strip of land stretching along the border. . . . Only a year after the disengagement, in October 2006, the IDF recognized that the tunnels in southern Gaza had become a serious and central threat. . . .
For months, the Egyptians have said that any Israeli approach to the corridor would be seen as a violation of the peace treaty, but even after the IDF took control of the Rafah crossing in less than a day in early May, Cairo maintained that the peace treaty remained stable.
Read more on Ynet: https://www.ynetnews.com/article/s14dqrfc0