RAFAH, Gaza Strip — Tens of thousands of Palestinian Arabs on foot and donkey carts poured into Egypt from Gaza today after masked gunmen used land mines to blast down a seven-mile barrier dividing the border town of Rafah.

The border breach was a dramatic protest against the closure of the impoverished Palestinian Arab territory imposed last week by Israel in response to increasing rocket attacks by Gaza militants. The closure cut off fuel and food supplies.

Jubilant men and women crossed unhindered by border controls over toppled corrugated metal along sections of the barrier, carrying goats, chickens, and crates of Coca-Cola. Some brought back televisions, car tires, and cigarettes and one man even bought a motorcycle. Vendors sold soft drinks and baked goods to the crowds.

They were stocking up on goods made scarce by the Israeli blockade and within hours, shops on the Egyptian side of Rafah had run out of most of their wares. The border fence had divided Rafah into two halves, one on the Egyptian side and one in southern Gazan.

A Palestinian Arab father of seven, Ibrahim Abu Taha, 45, was in the Egyptian section of Rafah with his two brothers and $185 in his pocket.

“We want to buy food. We want to buy rice and sugar, milk and wheat and some cheese,” Mr. Abu Taha said, adding that he would also get some cheap Egyptian cigarettes. He said he could get the food in Gaza, but at three times the price.

Police from the militant Islamic group Hamas, which controls Gaza, directed the traffic. Egyptian border guards took no action and imposed no border controls on those who crossed.

“Freedom is good. We need no border after today,” an unemployed 29-year-old, Mohammed Abu Ghazal, said.

President Mubarak of Egypt told reporters in Cairo his border guards originally had forced the Gazans back yesterday when they tried to cross.

“But today, a great number of them came back because the Palestinians in Gaza are starving due to the Israeli siege,” he said.

No starvation has been reported in Gaza. But many of the 1.5 million residents have faced critical shortages of electricity, fuel, and other supplies over months because Gaza has been virtually sealed since Hamas seized control of the territory by force from the rival Fatah faction in June.

“I told them to let them come in and eat and buy food and then return them later as long as they were not carrying weapons,” Mr. Mubarak said.

Egypt has largely kept its border with Gaza closed since the Hamas takeover amid concerns of a spillover of Hamas-style militancy into Egypt. But the government is under public pressure to help impoverished Gazans.

The collapse of the border, although likely temporary, is a boon to Hamas. It briefly eases the international blockade of Gaza and gives the Islamic militants possible leverage in demanding new border arrangements.

At the same time, it will likely raise tensions between Egypt and Israel, which fears militants and weapons will flood Gaza in growing numbers.

The supreme leader of Hamas, Khaled Mashaal, said from Syria that Hamas was willing to work out a new border arrangement with Egypt and the rival Fatah, led by the Palestinian Authority president, Mahmoud Abbas.

In Gaza, the Hamas prime minister, Ismail Haniyeh, called for an urgent meeting with Egypt and Fatah to work out a new shared arrangement for Gaza’s border crossings and suggested that Hamas would be prepared to cede some control to the Abbas government in the West Bank.

“We don’t want to be the only ones in control of these matters,” Mr. Haniyeh said.

But Hamas’s position was swiftly denounced by Mr. Abbas’s government. A Cabinet minister, Ashraf Ajrami, said Mr. Haniyeh’s call for participation was meant to sidestep Mr. Abbas’s demand that Hamas return all of Gaza to his control.

“Everything Haniyeh is saying is simply to exploit this situation to win political gains. … It is a part of the problem, not the solution,” Mr. Ajrami said.

Hamas seized control of Gaza by force in June, routing pro-Fatah security forces. Israel and Egypt sealed their border crossings with the coastal territory in response, and Mr. Abbas established another government in the West Bank. The two bitter rivals have not had formal contact since.

Israel and the West imposed an aid boycott on the Palestinian Arab government after Hamas won a parliamentary election and set up a government in early 2006. The sanctions have cut off roughly half of the estimated $1 billion in foreign aid and tax transfers from Israel. Since June, the West has been supporting Mr. Abbas and Gaza has received little direct foreign aid beyond the existing programs for Palestinian Arab refugees there.

Prime Minister Olmert of Israel warned he will not allow Gazans to live ordinary lives while Israelis next to Gaza are suffering from daily rocket attacks.

“We will not allow under any condition, or any situation, creation of a humanitarian crisis. We will not hit food supplies for children or medicines for the needy,” he said at the annual Herzliya Conference on security.

But he added: “Does anyone seriously think that our children will wet their beds at night in fear and be afraid to go out of the house and they (Gazans) will live in quiet normality?”

Israel also expressed concern that militants and weapons might be entering Gaza from Egypt amid the chaos, and said Egypt is responsible for restoring order.

Israel also is in a difficult situation. It cannot be seen as criticizing Egypt too strongly for fear of alienating one of the few Arab countries it has a peace treaty with.

“Israel has no forces in Gaza or Egypt, and the Egyptians control the border, and therefore it is the responsibility of Egypt to ensure that the border operates properly according to the signed agreements,” a spokesman for Israel’s Foreign Ministry, Arye Mekel, said.

“We expect the Egyptians to solve the problem,” he added. “Obviously we are worried about the situation. It could potentially allow anybody to enter.”

In Egyptian Rafah, a market stall selling pistols and ammunition clips for Kalashnikov assault rifles had no customers today. Weapons are generally brought into Gaza through smuggling tunnels under the Gaza-Egypt border.

An off-duty Hamas policeman, who only gave his first name as Abdel Rahman, said there was no need to buy weapons from Egypt.

“You can buy weapons in Gaza, guns and RPGs,” he said, adding that they were easier to find than Coca-Cola.

Palestinian Arabs have broken through the Egypt border several times since Israel pulled out of Gaza in 2005 and stopped patrolling the border. But none of the previous breaches approached the scale of today’s destruction, which demolished two-thirds of the seven-mile partition.

The border fence was erected by Israel after the outbreak of a second Palestinian Arab uprising in 2000.

The destruction of the wall began before dawn today, when Palestinian Arab gunmen began using land mines to blow holes in the border partition that divides Rafah, witnesses said. There were 17 explosions in all, Hamas security officials said.

Rafah residents said Hamas-linked militants had sliced through the metal wall with blow torches a month ago — weakening the structure so that it could fall easily when the blasts went off.

At first, Hamas and Egyptian security officers prevented people from getting through, witnesses said. But by morning thousands of Gazans had massed at the border and overwhelmed police began letting people cross.

Most Egyptian security and police were later pulled out from the immediate vicinity of the border, Egyptian security officials said.

In Washington, a White House spokeswoman, Dana Perino, blamed Hamas for the chaos in Gaza and said the instability was “very troubling” for Israel.

“It is Hamas’s actions of lobbing upwards of 150 rockets a day into their territory that has caused the blockade — has caused Israel to implement the blockade,” Ms. Perino said. “Hamas is not in control of the situation, they are not governing well, and the people of the — the Palestinian people are starting to realize that they do have a choice,” she added.

“The Palestinians living in Gaza are living under chaos because of Hamas, and the blame has to be placed fully at their feet.”

Today’s chaotic scenes came almost a week after Israel imposed a tight closure on Gaza, backed by Egypt, in response to a spike in Gaza rocket attacks on Israeli border towns.

Pictures of children marching with candles and people lining up at closed bakeries in a blacked-out Gaza City evoked urgent appeals from governments, aid agencies and the United Nations for an end to the closure.

Israel maintained that Hamas was creating an artificial crisis but nonetheless eased the closure slightly yesterday, transferring fuel to restart Gaza’s only power plant, and also sent in some cooking gas, food, and medicine.