Nearly half a century after a civil war in which a million people died, 27-year-old Okoli Ikedi is part of a new protest movement in southeastern Nigeria calling for an independent state of Biafra.

Such calls have become common since the leader of the group Ikedi represents in Enugu, the region's main city, was arrested in October, prompting thousands in the oil-producing southeast to join demonstrations in recent weeks calling for his release.

It's another challenge for President Muhammadu Buhari, who is grappling with a sharp slowdown in Africa's biggest economy, the bloody Boko Haram insurgency in the northeast and fears that militancy may resume in the oil-rich southern Delta region when an amnesty ends in December.