The tunnels have been around since the '80s, but were primarily used to smuggle weapons. Since 2007, the tunnels have been used to transport more benign goods.
"On the outside, on the 3-mile (5 km) fringe of Rafah town, are sandy hills dotted with tents, tarps and bulldozers. Underneath lies what passes for commerce, the surreptitious journey of goods that help keep the territory running.
'There is only one economy - there's a tunnel economy,' says John Ging, head of the U.N. Relief and Works Agency in the Gaza Strip. 'You have zero exports and zero commercial imports through the [Israeli-controlled] crossing points. All that is allowed in is humanitarian aid and supplies ... In terms of economic activity, there is no economic activity other than the tunnel economy.'"
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