EXPOSED: The biggest Hamas terrorist tunnel discovered. This massive tunnel system branches out and spans well over four kilometers (2.5 miles). Its entrance is located only 400 meters (1,310 feet) from the Erez Crossing—used by Gazans on a daily basis to enter Israel for work and medical treatment in Israeli hospitals. This tunnel system was a project led by Mohammad Sinwar, the brother of Hamas leader Yahya Sinwar, and the commander of Hamas’ Khan Yunis Battalion.