Israel's security agencies, by their own admission, were caught off guard when the Hamas militant group launched an all-front attack by air, sea and land on October 7, killing thousands of civilians and soldiers. The attack dealt a serious blow to Mossad, Israel's intelligence agency, and Shin Bet, Israel's internal security service, which had otherwise near impervious record in dissuading any potential assaults on the Jewish state. But what has emerged over the days, as Israel retaliates, is the devastating demonstration of the military expertise displayed by Hamas since gaining control of the Gaza Strip in 2007.
Here's how Hamas secretly built a 'mini-army' to fight Israel.