Hundreds of Hodeidah residents have been arriving in the Yemeni capital on a daily basis in a bid to flee an escalation in fighting in the western port city, a volunteer who helps internally displaced people to register in Sana'a has told epa-efe.

Khaled Saif, who helps IDPs register at an evacuation center after they have fled their homes, said over 45,000 people from Hodeidah had come to the capital in the past two weeks.

"In this center only, among others in Sana'a, we receive daily more than 300 displaced persons from Hodeidah," he told epa-efe.

Earlier in the month, United Nations High Commissioner for Human Rights, Michelle Bachelet, denounced the "unconscionable toll" the escalation of hostilities in Hodeidah was taking on a "deeply frightened and starving" population, according to a UN statement.

None of the people who had recently arrived in Sana'a had yet been given any food or shelter, according to the volunteer. "The IDPs are forced to depend on themselves for a month or two and then the authorities here provide some aid to those who continue to seek help."

But some chose to return home to war zones, regardless of the risk to their lives, according to Saif: "They have no choice but to do so."

Besides the lack of food and shelter, there was also a lack of medical care. According to the volunteer, over 80 IDPs at the center needed treatment for cancer, while others needed assistance for diabetes.

UNHCR spokesperson Shabia Mantoo told epa-efe the organization had "a variety of humanitarian programs across Yemen and we continue to reach refugees and displaced Yemenis with assistance, including those displaced from Al Hudaydah."

"There are indeed challenges in providing aid in essentially what is a war zone and we continued to voice our concerns on the impact of conflict on civilians as well as on aid operations," she added.

International aid is distributed by the Houthis in areas under their control, while coalition aid is distributed in government-controlled regions.

Yemen was currently gripped by what the UN has described as the world's worst humanitarian crisis, with 22 million people—75 percent of the population—in need of assistance and protection.

Khadija Mohammed Ahmed, 35, came to Sana'a with her husband and two children, as well as her sister's family. "We were forced to displace because of the fierce war there," she said.

They had been without clean drinking water and cooking gas since fighting broke out in Hodeidah five months ago, and left with nothing but the clothes they were wearing.

"We saw more bodies in the streets, especially a main street in Hodeidah which was full of corpses," she told epa-efe, adding that neighbors had been hit by stray bullets and shell shrapnel.

"The situation in Hodeidah is getting worse," she said.

Her family made its escape by car via several Houthi checkpoints. "Some tried to prevent us from continuing to flee, arguing that the city should not be left to the coalition forces."

While Khadija described their escape from home as "an adventure," the family was afraid coalition warplanes would target their vehicle.

Now in Sana'a, it was unclear what the family would do next. "We did not receive any aid at all," she said.

Taher Mohammed Ibrahim, 30, who also fled Hodeidah with his family, found himself in a similar situation.

"After arriving here in Sana'a, the Houthi-run aid group, responsible for the registration of displaced persons coming from Hodeidah, refused to register me, my wife and our two children as displaced," he told epa-efe. "So we can't receive any assistance."

At home, Taher used to own a large grocery store, but with many of his customers increasingly unable to pay, he went out of business.

"In Sana'a, we did not receive any aid from the authorities here or from humanitarian groups," he said. "They asked for identity papers and we do not have them."

Yemen has been locked in a political and military crisis since the popular regional uprisings of 2011, with the Houthis taking control of the capital Sana'a in Sept. 2014, expelling President Abd Rabbu Mansour Hadi, who is backed by Saudi Arabia.