Concerned about turmoil in Egypt and what Israeli military officials say is a rising threat along the country's southern border, Israel has embarked on building an iron barrier that will stretch nearly 140 miles from the Taba border crossing on the Red Sea north through the Sinai Peninsula to the Gaza Strip and the Mediterranean. It will be the largest manmade object in the largely unoccupied desert.
Israeli military officials, providing a tour of the fence last week, said the threat along the country's southern border with Egypt now was "as high as we have seen it."
"There are groups in Sinai right now planning terror attacks," the commander of the military unit assigned to defend the southern border said in a briefing. Under the conditions of the presentation, he could not be identified.
"There is criminal activity, smuggling, that is linked to the terrorism and can be used by them," he said.
Since the fall of Egyptian President Hosni Mubarak a year ago, the Sinai peninsula has become largely lawless.
Zeinab Abdo, 31, a mother of five who lives in a village outside Al Arish in the Sinai, said that years of mistreatment at the hands of Egyptian soldiers and police had led to chaos in the wake of the revolution.
"They were here everywhere, and now they're not," she said. "Everyone else is doing what they want now while they can."
Egyptian news reports contend that al-Qaeda and other groups have taken advantage of the decline in security to create bases in the Sinai.
The vast deserts and punishing terrain make policing the Sinai "a nightmare," Israeli officials said. They were quick to add, however, that they thought Egyptian authorities were "doing their best and have the full trust of the Israeli military."
Israeli officials have been careful to express support of Egypt's military sovereignty over the Sinai.
The commander said tensions had calmed since August, when a group from Sinai crossed into Israel to launch attacks that killed eight Israelis. In an ensuing gunfight, Israeli soldiers shot and killed five Egyptian border guards, setting off a diplomatic row that was quelled only after Israel apologized for the guards' deaths.
The incident took place within eyesight of where Omar was welding together Israel's newest barrier.
"They are pushing us to work quickly," he said.