A Yemeni drags a sack away from a truck that was allegedly destroyed by an airstrike of the Saudi-led coalition targeting a wheat convoy. (Abdul-Rahman Hwais/EPA)

The fighting in Yemen threatens to cause widespread hunger and thirst and displace huge numbers of people, creating another humanitarian disaster in a region already reeling from the crisis in Syria, according to analysts and aid workers.

The impoverished Arabian Peninsula nation of 25 million people was struggling with alarming malnutrition levels even before an offensive by Shiite rebels, called Houthis, prompted a military intervention last month by a coalition led by Saudi Arabia.

Now, the Saudi-led coalition’s airstrikes as well as the fighting at the country’s airports and seaports are impeding access to food and other supplies.

According to the United Nations and humanitarian aid agencies, major urban centers, including the southern city of Aden, which has a population of about 1 million, may run out of drinking water.

The fighting has displaced thousands of Yemenis, and a continuation of the unrest could produce waves of refugees reminiscent of the flight of Syrians from cities and towns engulfed in that country’s civil war, analysts and aid workers say. About 4 million people have poured out of Syria and 6 million more are internally displaced because of the fighting.

Looking to exploit Yemen’s chaos are extremist groups such as al-Qaeda in the Arabian Peninsula (AQAP) and the Islamic State, said Fawaz A. Gerges, professor of Middle Eastern politics at the London School of Economics.

“If Yemen descends into all-out war, which is a likely scenario, we could witness a greater humanitarian crisis than that of Syria, in terms of refugees and mass starvation,” he said. “You could end up with al-Qaeda being the main winner after this conflict.”

The Houthi rebels have seized vast tracts of Yemeni territory and in February toppled the U.S.-backed government of President Abed Rabbo Mansour Hadi. The Saudi-led coalition, which has conducted air attacks against the Houthis and threatened a ground assault, hopes to restore Hadi to power. The embattled president fled Yemen last month for Saudi Arabia, which views the Houthis as proxies of Shiite Iran.

Sitara Jabeen, a Geneva-based spokeswoman for the International Committee of the Red Cross, said that on Sunday, the Saudi-led coalition gave the organization permission to fly two planes to Yemen carrying aid workers and 48 tons of medical supplies. But the Red Cross has not yet been able to charter aircraft that will travel to the war-torn country, she said.

Adel al-Jubeir, Saudi Arabia’s ambassador to the United States, said in an interview that “we are engaging with international relief organizations to facilitate” the provision of aid. But he indicated that delivery of supplies by plane was unlikely, because Saudi airstrikes have destroyed runways and have “pretty much shut off Yemeni airports.”

Fears of total breakdown

The United Nations estimates that more than 500 people have been killed in the fighting in the past two weeks. Meanwhile, supplies of food, fuel and water are dwindling, and government services such as health care are deteriorating rapidly.

Julien Harneis, the Yemen representative for UNICEF, said shrinking supplies of fuel are threatening the ability of municipalities to run ambulance services and of hospitals to refrigerate vaccines.

In addition, the lack of diesel fuel means that pumps cannot draw well water for this chronically parched country. For years, experts have warned that Sanaa could be the first capital in the world to run out of water.

Already, intense fighting in Aden has stopped the pumps, depriving most of the city of drinking water. “We’re worried that this system will totally break down shortly; Aden is a dry, hot place, and without water people will really suffer,” Harneis said.

The city also is struggling with prolonged power cuts.

Grant Pritchard, Oxfam’s director in Yemen, expressed concern about “a humanitarian disaster on our hands in the coming weeks and months” if the fighting does not stop. Even before the current bout of fighting, he said, about 16 million Yemenis relied on humanitarian assistance. About 10 million did not have enough food to eat, while 9 million lacked basic medical care and 13 million did not have access to clean drinking water.

Most international aid workers have left the country because of the danger, and their organizations have had to scale back operations. Foreign businesses such as oil companies have suspended work, while money from abroad — a crucial source of help for millions of Yemenis — has stopped flowing.

The country’s meltdown has left many of the nearly 2 million Yemenis working next door in Saudi Arabia desperate to send cash but blocked by a breakdown in the system of money exchange used to transfer currency to Yemen.

Fawaz Abdulrahman Abdullah, 22, an employee at a hotel in Riyadh, the Saudi capital, said he nearly broke down in tears the last time he reached his family by telephone in their village outside Aden.

“They begged me, ‘Where is the money?’ ” he said. “I told them, ‘I can’t find any way to send it.’ ”

He looked for someone traveling to Aden who could carry the cash in hand. But the Saudi military has closed the border.

Dwindling food supplies

For those struggling in Yemen, such as Mohammed Alawi Mohammed, a 34-year-old father of two, a lack of food is a major concern. Supermarket shelves are increasingly bare. According to some estimates, Yemen imports more than 90 percent of its food.

“I worry that even basic foods will vanish and prices will rise significantly,” said Mohammed, an IT consultant.

Saudi Arabia has agreed to create a special committee to coordinate with aid groups on the transport of supplies to Yemen, according to Brig. Gen. Ahmed Asseri, a Saudi military spokesman.

Even if food were arriving unimpeded from abroad, though, transporting it inside Yemen has become increasingly difficult because of fighting and airstrikes, said Abdul-Ghani al-Iryani, a Yemeni political analyst. That has caused a spurt in prices of basic goods in rural areas by as much as a third, a huge burden in a country where nearly half the population lives on $2 a day or less, he said.

“If the situation deteriorates further, it will be a full-blown famine,” Iryani said.

Collapsing law and order

This has added to his concerns about a refugee crisis that could compel masses of people to seek safety beyond Yemen’s borders. There are unconfirmed reports that Yemenis have begun fleeing across the Gulf of Aden to Somalia.

“If there is a total breakdown of law and order, we should expect millions of people going towards the Saudi and Omani borders, trying to find refuge,” Iryani said.

Adam Baron, a Yemen analyst and visiting fellow at the European Council on Foreign Relations, said that such a breakdown has been occurring for some time but that the Saudi assault has accelerated it.

He referred to the disintegration of the military and deteriorating authority in cities such as Aden, where civilians are arming themselves for street-by-street battles against Houthi rebels.

“We are seeing real signs of collapsing order and the militiafication of Yemen,” he said.

Filling the void, he added, is AQAP, al-Qaeda’s most formidable affiliate, which uses Yemen to stage attacks against the West. In recent days, the group has come close to seizing control of Yemen’s fifth-largest city, Mukalla. On Thursday, it freed as many as 300 prisoners in the coastal city, including a senior leader of the group, after storming the jail.

In the capital, Bandar Mohammed Senan, 36, a father of two, certainly fears AQAP. But a bigger concern is how to feed his young children, especially after the Sanaa television channel where he works was forced to close because of the Saudi bombings and a cutoff of electricity.

“What are we going to do if food prices go up? How will I be able to manage?” he said. “The situation is horrible.”

Ali al-Mujahed in Sanaa, Brian Murphy in Riyadh and Karen DeYoung in Washington contributed to this report.

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