In Ethiopias Endabaguna refugee camp, rows of gaunt Eritreans clad in rubber sandals give vent to their exasperation after days of trekking and dodging soldiers in an attempt to escape failed crops, hunger and an autocratic government.

Over 12 million people across the Horn of Africa are struggling from the region's worst drought in decades, but secretive Eritrea is the only country to deny it has been affected by the crisis.

"This year I farmed, but there was lack of rain. I dont know whats going to happen, only God knows," said Mehreteab, a refugee.

He escaped from the army, risking death or jail if caught crossing the heavily militarized border, leaving his wife and three children behind.

"There is no food and no grain in the home," he said. "I dont have any idea whats going to happen to them."

Camps in northern Ethiopia receive about 900 refugees every month from Eritrea, one of the regions most isolated countries.

A former colony of Italy and then part of Ethiopia, Eritrea fought a 30-year war with Ethiopia and only gained independence in 1991.

A subsequent border conflict with Ethiopia from 1998-2000 still simmers. Former rebel leader Issaias Afewoki, who has been in power since 1991 without elections, has cracked down on all dissidents and severely restricted press and religious freedom.

The majority of those arriving in the Ethiopian camps are young men escaping conscription, which forces men above 16 to serve in the military for decades on minimal pay.

The UN recently called for tighter economic sanctions after releasing a report linking Eritrea to a failed bomb plot at the African Union.

According to satellite imagery from the weather monitoring group FEWSNET, rainfall in parts of Eritrea this year has been "below average" - less than 10 percent of normal levels in some areas.

Aid workers admit it is nearly impossible to know just how gravely the Eritrea is affected because access to information is so limited in the country where the only media is state-run.

"Its been a black hole for us, we dont know whats going on there," said Matthew Conway, spokesman for the UN humanitarian coordination office in Nairobi. "But thats not to say its not happening."

The US ambassador to the United Nations has said she is "deeply concerned" that Eritrea is facing extreme hunger, and urged the government to allow humanitarian access.

"The people of Eritrea who most likely are suffering the very same food shortages that were seeing throughout the region are being left to starve," Susan Rice told reporters in New York.

And much like other countries in the region, such as Ethiopia and Kenya, Eritrea is vulnerable to increased food prices, exacerbating the crisis.

According to the UN agriculture agency, global food prices jumped 33 percent in the last year.

"High international prices affected every country in the world, so from that you can assume Eritrea is affected," said Shukri Ahmed, an economist at the Food and Agriculture Organization.

Fiercely self-reliant Eritrea stopped sending market information to FAO about three years ago, Ahmed said, so it is impossible to know how much food prices have risen in the country.

"Unfortunately, we dont have any information on the ground," he told AFP by phone from Rome.

Over half of Eritrea's food is imported, the FAO estimate, leaving it vulnerable to market fluctuations for staples such as sorghum and maize.

Eritrean refugee Berhane, 35, said the cost of food has surged in recent years, though wages have remained the same.

Intermittent work as a labourer earned him about $5 per day. But the cost of grain is about $3 per kilo and a sheep is about $170, more than he could make in a month, he told AFP.

"How is someone with no money or daily work supposed to buy this?" he asked. "It is too expensive."

Facing steep food costs, he relied on a small plot of land to feed his family. But the rains were two months late this year and his harvest failed.

"The government doesnt do anything. Nothing. There are no rations," he told AFP.

The Eritrean authorities deny the country is facing food scarcity.

"This nonsense about a hidden famine in Eritrea is utterly false," the Eritrea's information ministry said in an online statement last week.

Instead, Asmara claims last year's harvest was the best in a decade, while state run media heap praise on government-run food security programs.

But refugee Gebrielxavier, 25, said this is not true. He left Eritrea last November because his crop failed, he could not find work and his family went hungry.

"We couldnt live. We were famished," he said. "And the government? It did nothing."

He is now running a cafe in the refugee camp, where he earns less than $2 a day and relies on UN food rations, but says he is still better off.

"I got my freedom," he said.