JOHANNESBURG, 12 May 2011 (IRIN) - Thousands of frustrated Ethiopian and Somali asylum seekers trying to make their way to South Africa have been marooned in overcrowded camps in northern Mozambique since the government introduced measures limiting their movements.

The Maratane Refugee Camp in Nampula Province, which normally accommodates around 5,500 long-term residents from the Democratic Republic of Congo, Burundi and Rwanda, now has a population of over 10,000, while an additional 1,000 asylum seekers are staying at a temporary site in the coastal town of Palma, near the border with Tanzania.

"We did our best to expand facilities - building additional shelters, [drilling] boreholes, and by procuring food and non-food items, but given the sheer volume of the numbers, we're obviously overwhelmed," said Girma Gebre-Kristos, country representative of the UN Refugee Agency (UNHCR) in Mozambique.

A steady stream of Ethiopians and Somalis started arriving in Mozambique in 2010, mostly by boat, but as long as the number of new arrivals at the Maratane Camp roughly equalled the number of departures, authorities were able to cope, Gebre-Kristos told IRIN.

However, this changed unexpectedly at the beginning of 2011, when the number of new arrivals increased significantly and the government of Mozambique put in place strict measures controlling the movements of asylum seekers outside the camp.

Gebre-Kristos said groups of Somalis and Ethiopians making their way south towards the border with South Africa had been picked up by police and returned to Maratane.

Aderito Matangala, acting head of the National Institute for Refugee Assistance (INAR), the local government counterpart of UNHCR, explained that while the law in Mozambique allowed asylum seekers freedom of movement, they first had to complete a registration process at the camp, which took three months.

"The existing law gives [asylum seekers] freedom of movement even before being granted refugee status," Matangala told IRIN, and many Somali and Ethiopian asylum seekers chose to come to Mozambique because of its reputation for treating refugees well.

"My personal view is that not all of them want to go to South Africa," he said, noting that some of the new arrivals were economic migrants rather than genuine asylum seekers.

Reports in recent weeks that the local police commander in Palma had deported about 150 Somali and Ethiopian asylum seekers to Tanzania, and that four Somali asylum-seekers were shot dead by border police on 29 April in Cabo Delgado, Mozambique's most northerly province, suggest that police and immigration officials are not always aware of their country's obligations to asylum seekers. The government is investigating the shooting and the deportations.

UNHCR and INAR are appealing for help to deal with the food, shelter, water and sanitation needs of the new arrivals in Maratane and Palma. So far the World Food Programme and the Mozambique Red Cross have stepped in with contributions of tents and food.

However, the situation in Palma remains dire. The camp is located next to a swampy, mosquito-infested area with no potable water, but Gebre-Kristos said an alternative location had been identified and would be ready soon.

Besides a lack of infrastructure, the Maratane Camp is struggling to balance the needs of the new arrivals with those of more established residents from the Great Lakes region, many of whom are involved in self-reliance projects and no longer need food assistance.

By contrast, said Gebre-Kristos, the newer residents were often "frustrated and angry young men who think their journey to South Africa has been interrupted".