A source in the Presidency said the group had been operating within some North Central and South-South states, using foreign terrorists.
They are also believed to be recruiting young men into their fold and killing innocent people, thereby creating tension along ethnic, religious and regional fault lines.
It was gathered that “a good number “of the Islamic State terrorists have been arrested not only in the Benue valley but significantly in many towns in Edo State, such as Akoko Edo, Okpella and Benin, the state capital. They have also been found in Okene in central Kogi State.
The source said: “Security service organisations, including the Department of State Service, (DSS) in a report submitted to President Muhammadu Buhari, identified an Islamic State in West Africa network operating within some North Central and South-South areas”
The source said the discovery was made following the arrest of many suspected attackers made up of Fulani herdsmen, government-sponsored militias, militants and other miscreants in Benue State.
The source, who spoke on condition of anonymity because of the “sensitivity” of the matter, said among those in custody were many who spoke Nigerian languages.
“They mostly speak the French,” the source said, adding: “This is the first time that security officials have confirmed that Islamic State in West Africa members are operating as a unit in Nigeria and the level of their penetration of the country.”
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He went on: “It is understood that the cell, which has members in different parts of the country concentrates on recruiting young men to fight for the Islamic State in West Africa by unleashing the cold-blooded murder of innocent citizens.
“There was intelligence that they had planned attacks in the country, before and during Christmas and the New Year festivities. Their bombing targets included fuel depots, foreign missions, the police and military establishments.
“Their network is very wide. But so much was achieved by the DSS, which made a significant number of arrests in the last two months that helped to preempt those attacks. This helped to save Nigeria from the spate of major terrorist attacks witnessed elsewhere that were syndicated by ISIS worldwide.”
The reports submitted to the Presidency, he said, also revealed that security officials now fear an influx of other ISIS members into many parts of the country.
“We are learning more and more about this complex and sophisticated network. This is the main reason why the secret service is not parading those suspects so far arrested. It has become clear to us, by now, that the challenge facing this country is a serious one.”
Senior Special Assistant to the President on Media and Publicity Mallam Garba Shehu confirmed that President Buhari had been receiving “report upon report on the situation in Benue and other states”.
He said although the DSS had recorded a lot of success lately, he had not been briefed on any of the reports.
In Benue State, no fewer than 73 persons were killed by gunmen, who were said to be herdsmen. In Taraba, 55 persons died and 200 homes were torched. Both incidents occurred early this month.