In Nigeria, a former leader of a militant group that claimed responsibility for a dual car bombing in which 12 persons were killed has been arrested in Johannesburg. Henry Okah, an ex-leader of the Movement for the Emancipation of the Niger Delta was arrested sometime after the bombings yesterday. A spokeswoman for Nigeria's secret police said they had intelligence input beforehand that an attack was imminent but were unable to stop the bombings that targeted celebrations surrounding Nigeria's 50th anniversary of independence from Britain.