Thousands of people are fleeing to Chad, Niger and Cameroon as the crisis in neighbouring Nigeria deepens, the UN refugee agency has said.



UNHCR officers said on Tuesday that up to 3,000 refugees had arrived in Cameroon amid reports of at least 6,000 people escaping to Niger over the past weeks as the confrontation between the Nigerian army and the Boko Haram group intensified in the country's northeast.



"The immediate priority is to secure food and shelter as refugees are entering extremely harsh and difficult areas," Fatou Lejeune-Kaba, Africa spokesperson for UNHCR, told Al Jazeera.



Cameroon had initially closed its border with Nigeria to prevent members of Boko Haram to enter, but after June 11, the border was re-opened, the UNHCR said.



With fighting only intensifying, and about 3,000 people arriving between June 11-13 alone, there are concerns that this may be the start of a large exodus from the region.

New arrivals

The government of President Goodluck Jonathan embarked on a major military offensive on May 15 to root out the Boko Haram group responsible for a series of bloody attacks in the African country over the past four years, killing hundreds of people.

A state of emergency was imposed on the Adamawa, Borno and Yobe states in a response to the rising attacks, raising concerns of human rights activists of possible violations against civilians.

The UNHCR said crossings into Cameroon began a week ago, with most of the refugees being women and children.

Refugees are being hosted in churches and schools, and relying on food from the local population.



We are working with the authorities to relocate the refugees to safer places away from the border, away from possible fighting, Lejeune-Kaba said.

Meanwhile in Niger, trucks carrying aid was dispatched from Niamey to the southeastern Diffa region, where more than 6,000 people have arrived from northern Nigeria in the past weeks.

This includes Nigerian nationals as well as returning Niger nationals and others nationalities.

Most of the new arrivals in Niger traveled on foot from rural villages across the border and from Maiduguri and Baga towns.

In Chad, refugees have been arriving in small numbers, saying their homes were destroyed after the military accused them of harbouring Boko Haram fighters.

Military offensive

Aid organisation and media have been banned from accessing the frontlines and there have also been complaints that mobile networks were shut down since the offensive started, effectively cutting off the region from the rest of the country and the world.

"The situation is not getting the attention it deserves," Lejeune-Kaba, from the UNHCR, said.

In late May, Amnesty International urged Nigerian authorities not to use the state of emergency in the north eastern regions as an excuse to commit human rights violations.

Amnesty said detainees were being held without access to lawyers, or being officially charged with a crime.



The human rights group also claimed that services had come to a standstill with schools closed and some towns resembling 'ghost towns'.



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