WASHINGTON AND RAFAH, EGYPT — Some of them are said to be big enough to accommodate railroad cars. They may reach a depth of 60 feet, and are reported to be equipped with cables and electric motors that move food, fuel -- and probably some of the heaviest rockets that Hamas aims at Israel.
They also are one of the main reasons fighting is continuing in the Gaza Strip.
As Israeli officials debate how far to press their campaign in Gaza, one of their chief goals is finding a way to crimp or permanently halt the flow of arms to Hamas through a complex of tunnels under the territory's border with Egypt.
While ground forces battle Hamas fighters in the streets, Israeli warplanes have pummeled targets in Gaza near Rafah, the town that straddles the Gaza-Egypt border. Israel's demand to block arms shipments through the so-called Philadelphi corridor, the strip of land separating Gaza and Egypt, is a central point in cease-fire talks.
"The tunnels are important, probably to the point that a preponderance of weapons have come through those tunnels," said a senior U.S. military official who has seen classified intelligence reports on Hamas arms flows.
For residents of Gaza, however, the tunnels bring far more than arms. The territory's borders have largely been sealed since Hamas took control of the territory in 2007. The tunnels are the main conduit for normal commerce and a lifeline for food and medicine.
Smuggling through the tunnels is also a primary source of income for Bedouin tribes long neglected by the Egyptian government. One smuggler, who gave his name only as Abu Mohammed, said that gasoline and food made up the bulk of his business.
Palestinians involved in cease-fire negotiations want to see the overland border with Egypt reopened. "As long as there's a blockade around Gaza, the tunnels will remain," Abu Mohammed said.
On the Israeli side, military officials and politicians have made clear that they see the blocking of the tunnels as a prerequisite to any cease-fire.
"We must reach, at the end of the war, a situation in which this arms smuggling is stopped," Yossi Peled, a general in the Israeli reserves and former head of the Israel Defense Forces' northern command, said this week on Israeli radio. "If we do not achieve this, then one might very well ask why it was that we embarked on this war to begin with."