An Egyptian security crackdown has severely disrupted smuggling to the neighboring Gaza Strip, causing a fuel shortage, doubling the price of building materials and shutting down some construction sites in the Hamas-ruled territory.

Egypt's military clamped down on the lawless Sinai Peninsula, which abuts Gaza, in the run-up to mass protests planned for Sunday by Egyptian opposition activists trying to force out the country's president, Mohammed Morsi.

It's not clear if the Sinai lockdown is temporary or signals a tougher security regime aimed at restricting smuggling through tunnels running under the Egypt-Gaza border in the long term. That would have a devastating effect on Gaza, which has relied on smugglers since Israel imposed a border blockade following the rise to power of the Islamic militant group Hamas in 2006.

The Sinai campaign began this month when Egypt's military sent troop reinforcements and set up dozens of roadblocks across the sparsely populated stretch of desert that runs from the Suez Canal to the Gaza border. As a result, Egyptian trucks carrying cement, steel rods, fuel and other goods could no longer reach the Gaza tunnels.

"Nothing can get to the (tunnel) area," said Abu Khaled, 44, a tunnel operator in Gaza. "We are like a dry lake now. ... We all pray that this will end soon."

Gaza has only small reserves of cement, steel and other materials for private construction. With few exceptions, Israel bans such goods for fear Hamas will divert them for military use.

In response to the Sinai clampdown, the price of cement has doubled to $220 per ton, forcing some of the more than 200 private construction sites in the territory to shut down, contractors said. A shortage of cheap Egyptian fuel is forcing Gaza motorists to buy more expensive Israeli imports.

For now, Gaza's Hamas government is keeping silent.

Hamas and Morsi's Freedom and Justice Party share the same roots in the region-wide Muslim Brotherhood, and Hamas leaders appear reluctant to add to Morsi's troubles by complaining publicly about the disruption of smuggling.

The Egyptian military is known to be wary of Morsi's close ties to Hamas, viewing it as a threat to Egypt's public security. The military is bound to play a pivotal role in the current showdown between Morsi and his opponents, with both camps trying to ensure its support. Hamas would undermine Morsi by demanding an end to the Sinai crackdown now.

Mahmoud Zahar, a Hamas leader in Gaza, said the movement is aware of Morsi's domestic problems. "We are waiting until the administration (will) be more solid and stable" before raising demands for a new border regime, he said.

A collapse of the Morsi government would deal a major setback to the Brotherhood, including Hamas.

The Arab Spring uprisings of 2011 swept the Brotherhood to power in Egypt, Tunisia and Libya, easing Hamas' political isolation in the region. Hamas, which has killed hundreds of Israelis in suicide bombings and other attacks, has long been shunned by Israel and the West as a terrorist organization. Morsi's Western-backed predecessor, Hosni Mubarak, had joined Israel in enforcing the Gaza border blockade — though he turned a blind eye to the tunnels because of the Egyptian public's sympathy for the Palestinians.

Hamas' hopes of normalization on the Gaza-Egypt border following Morsi's inauguration a year ago have not materialized. An Egyptian-brokered cease-fire ending eight days of fighting between Israel and Hamas last November called for new border arrangements, but nothing has changed so far.

The land crossing between Egypt and Gaza is not equipped to handle cargo, and opening the border to trade would have violated previous international agreements, a risky step Morsi did not want to take early on in his presidency. Instead, he eased passenger travel slightly and allowed limited construction materials — those intended for large Qatar-funded projects in Gaza — to be transported above ground.

As a result, Gaza continued to rely on tunnels, mainly for cement, gravel, iron rods and fuel. Most consumer goods have been shipped through an Israeli cargo crossing since Israel eased its border restrictions three years ago.

In normal times, about 70 tunnels are active — most for cargo, but some also for travelers evading Egyptian border controls. Tents or in some cases houses cover the openings on the Gaza side of the 14-kilometer (nine-mile) border. Hamas levies customs on smuggled imports and has turned the tunnel zone into a closed bonded area, with a line of checkpoints searching cargo trucks.

During a visit this week, the tunnel zone — normally humming with the sound of generators and the rumbling of trucks — was quiet. Only a few trucks loaded goods that had crossed the Sinai before the clampdown.

Egyptian military officials said the immediate target of the Sinai campaign is to keep out militants who might sneak into Egypt through the tunnels to spread chaos. Egyptian authorities never had a strong presence in the remote peninsula, but the last vestiges of law and order broke down after the 2011 uprising.

Militants have stepped up attacks in the Sinai, including last year, when 16 Egyptian soldiers were killed near Gaza. In addition, Bedouin tribal gangs are involved in smuggling and other criminal activities.

Egyptian security officials met with their Hamas counterparts at the start of the current security campaign. They are working together to minimize any threat at a time when Morsi is facing the most serious challenge to his rule, said officials from both sides who spoke on condition of anonymity because they were not authorized to discuss their talks with reporters.

Egyptian officials, however, said the reason they are virtually sealing off the Sinai is that Hamas is not doing enough.

Gazans are used to frequent shortages, and those involved in cross-border trade expressed hope the current crisis would blow over quickly.

"Everyone here and in Egypt is waiting to see what will happen (after Sunday), and we all pray for the good," said Nimr Rabah, a Gaza contractor who had to shut down two of his sites.

Abu Khaled, who imports gravel, expressed understanding for Egypt's security concerns, but said the closure is hurting a lot of people. He said 18 families on both sides of the border depend on his tunnel for their livelihood.

Truck driver Abu Tawfik, who transports cement from the tunnels to construction sites, said he has been idle for the past week. As a result, construction work is also slowing down, hurting one of the pillars of Gaza's shaky economy.

The construction industry has recovered slightly since the height of Israel's border blockade, employing about 20,000 people.

Nabil Abu Muaileq, chairman of the contractors' union, said there are more than 200 private construction projects, including homes and apartment buildings, in addition to projects by the Gaza government and international aid groups.

Rabah, the contractor, said the cement shortage forced him to stop work several days ago on a home and an apartment building. "We were told by the tunnel dealers they were unable to secure what we need due to the security arrangements" in Egypt, he said.

An Egyptian intelligence official said the crackdown on smuggling likely will continue, if perhaps not at the current level, even if Egypt's current political crisis is resolved.

The official, who spoke on condition of anonymity because he was not authorized to brief reporters on internal deliberations, said any decision to shut down the tunnels completely would have to come not from the military, but from Morsi.


Associated Press writers Karin Laub and Mohammed Daraghmeh in Gaza City contributed reporting.