LAGOS, Nigeria — Extremists from three neighboring countries are fighting in Nigeria’s northeastern Islamic uprising, according to an alleged captured fighter, reinforcing fears that one of Africa’s most powerful Islamic militant groups is growing closer to al-Qaeda affiliates and that radical movements are spilling across national boundaries.
“We do have members from Chad, Niger and Cameroon who actively participate in most of our attacks,” said a young man presented to journalists Friday night by Nigeria’s military as a captured fighter of the Boko Haram terrorist network.
The claim of foreign fighters indicates the growing influence of Boko Haram, which started out as a machete-wielding gang and that now wages war with armored cars, rocket-propelled grenades and improvised explosive devices. The group’s mission is to force all of Nigeria — Africa’s largest oil producer and a country of 160 million that has almost equal numbers of Christians and Muslims — to become an Islamic state.
The young man refused to give his name, for fear that his family would be targeted. His account sheds new light on life inside the shadowy Boko Haram.
He said religion did not figure in his life as a Nigerian Islamic warrior. He added: “I did not see any act of religion in there. We are just killing people, stealing and suffering in the bush.”



