Niger removes 4,000 Nigerian refugees from Lake Chad island

(Reuters) - Niger has evacuated thousands of Nigerian refugees sheltering from Boko Haram fighters on Lake Chad's Karamga island, a military official told Reuters on Tuesday, as the armies of four west African nations battle to quash the Islamist militants.

A regional governor in southern Niger said last week that the refugees should leave after Boko Haram fighters killed scores of the country's soldiers and civilians during a dawn ambush on the island on April 25.

The executive secretary of the State Emergency Management Agency in Yobe state, Idi Jidawa, said that 4,000 displaced Nigerians were in the process of being sent home.

Lake Chad's islands, which lie in dense swampland, have been used by Boko Haram to mount surprise attacks on the bordering countries: Chad, Cameroon, Niger and Nigeria.

The group, which is fighting to create a caliphate in west Africa, has killed thousands and uprooted 1.5 million people from north eastern Nigeria, many of whom have found relative security in neighboring countries including Chad and Cameroon.

The Nigerian refugees were already on their way back home and would arrive at the frontier town of Geidam in Yobe state on Wednesday, said Jidawa. A Nigerian security official, who declined to be named, confirmed the news.

"Though NEMA (National Emergency Management Agency) is in charge, we are assisting them in the exercise of profiling and documentation," Jidawa said.

With the help of regional armies, Nigerian troops have cornered Boko Haram fighters into Sambisa Forest, where it has rescued nearly 700 women and children that the group had held captive.