COSTELLO: So the attacks on Gaza by Israel are focused on the tunnels that reach from Gaza into Israeli territory and the numbers and complexity of the tunnel system have presented additional challenges and risks for Israel. Martin Savidge has more for you.</s>MARTIN SAVIDGE, CNN CORRESPONDENT (voice-over): The same thing that has challenged and slowed Israeli soldiers in Gaza is now spilling the war out of Gaza into Israel. Tunnels. Early Monday, Israel Defense Forces say two terrorist squads of Hamas militants used the tunnels to infiltrate from northern Gaza into Israel near the town of Sderot. Possibly intending to launch an attack on civilians. This Israeli military video said it showed five of those Hamas fighters, first crouching in the brush then firing on nearby Israeli soldiers, their rifles raised and recoiling after each shot. At one point, one of the men can be seen reloading. Then as the Israelis returned fire, the militants appear to retreat back to their tunnel when an Israeli airstrike hits. The incident forced area roads to close, residents to shelter in their homes and tied up security forces for hours. The military says 10 Hamas militants were killed and a number of Israeli soldiers wounded. Inside Gaza, the IDF says a well-organized and deeply entrenched network of tunnels has hampered Israeli movement allowing militants to pop up unexpectedly, firing on soldiers or tossing grenades before dropping back out of sight. Israeli military officials refer to the underground work, says lower Gaza and suggest at least some of the war is being waged under ground. So far Israel says it's discovered 14 tunnels each with multiple access points. Engineers methodically worked to destroy them using heavy earth moving equipment or explosives. Israel believes there are many more tunnels yet to be found. And as soldiers battle through Gaza streets, another danger lurks just beneath their feet. Martin Savidge, CNN, Jerusalem.
Israel Intent on Destroying Hamas Tunnels