In the southwest corner of the Arabian peninsula, tens of thousands of people have fled fighting between Yemen's government forces and Shiite rebels. The flow of displaced people increased dramatically in recent days, as Saudi Arabia joined in the conflict with air and ground attacks following a rebel incursion across the border.
At the main U.N. camp in northwestern Yemen, aid workers are struggling to cope with a rising tide of displaced families from the civil war.
Just outside a tiny village of cement stores and stick-and-mud dwellings, acres of tents stretch across the reddish-brown dirt, growing layers of dust as soon as they are erected. The camp is situated on the hot and arid northwestern plain of Yemen, six hours of hard, mountainous driving from the capital, San'a.
Mountain-born farmers and shepherds of the Saada governorate who fled the fighting are trying to learn the strange customs of their new home, the Mazrak camp. About 8,700 people are living at the camp, according to the latest numbers from the U.N., and 11,000 displaced persons are sheltered by host families and communities in this part of Yemen.
A total of 175,000 people have been displaced since 2004, the U.N. estimates.
At the World Food Program tent, a jostling knot of people seems like chaos, but it is an aggressively maintained line. These displaced people are waiting for the monthly food distribution of wheat, beans, sugar, cooking oil and salt. But to get it, camp residents must be registered, and for some that is a problem.
Salama Ahmed, wearing the full black Islamic veil, says she and her 15 family members fled their home near the Saudi border when the rebels — who are known by the family name of their leader, Houthi — moved in and Yemeni army forces attacked.
She explains that they first walked into Saudi Arabia, where they were welcomed. But when the Houthis crossed the border into Saudi territory last week, the Saudis rounded up all the Yemenis they could find and sent them back to Yemen — in her case, without identification cards.
For now, that means no registration, no food and no tent. The unregistered people borrow food from those who have it and sleep where they can.
Often, that means bedding down next to a sheep, goat or cow. For these people, animals are a main measure of wealth, and war or no war, they weren't about to leave them behind.
Ali al-Gaisa, a slender young man with a scarred leg, can confirm at least one Saudi rocket landed on the Yemeni side of the border. He is careful to include livestock casualties in his story of fleeing the conflict.
"By God, it was a problem. We were just sitting in the house when a Saudi rocket hit. I don't think there were any Houthis nearby. My brother was hit by shrapnel in the neck, and you can see my leg here. And the sheep, about 20 head of sheep were killed," he says.
At the UNICEF medical tent, Dr. Fakherideen al-Mahalbi says they have had three infant deaths and are tracking 622 cases of severely malnourished babies. He says some of the women don't understand that they have to keep bringing the babies back until they are out of danger, so he sends volunteers out to look for them.
"Try to advise the mothers and change the mind of the mothers and the families to bring the babies to us," he tells them. "Because the babies are severely malnourished, and if you left them without followup, they may die."
Mai Barazi, team leader for the U.N. refugee agency at the Mazrak camp, says relief groups are careful to respect the traditions and customs of the displaced. But as she checks in on the construction of the camp's new women's center, she also hopes they can help women play a greater role in making the camp work.
"Socially and tradition-wise, the women are not as active, they don't have a lot of access to services, they are not decision-makers, so we thought this is the best way they can come, they can feel safe, they can talk, and hopefully we'll also have some literacy classes later on," she says.
For these Yemenis, politics are a distant concern. The Houthi rebels may be Shiites in a largely Sunni country, but to these people, many of them minority Shiites themselves, the Houthis are just another criminal gang.
One political question does interest them, though — whether the Saudi involvement will make this conflict better or worse — because that will determine how soon they can get back to the cool air of the mountains and what is left of their homes.