Odi — an Ijaw town of about 15,000 people in Kolokuma/Opokuma Local Government Area, Bayelsa State — was the site of an Ijaw Youth Council (IYC) gathering following the Kaiama Declaration of December 1998, which had demanded resource control and the withdrawal of federal armed forces from Ijaw land. On 5 November 1999 twelve Bayelsa State Police officers were killed by a militant Ijaw youth group operating from Odi; the suspects fled into the surrounding creeks.
President Olusegun Obasanjo, seven months into the Fourth Republic, issued the Bayelsa State Governor Diepreye Alamieyeseigha a fourteen-day ultimatum to produce the suspects. On 20 November 1999 — before the ultimatum had expired — the 2nd Mechanised Battalion of the Nigerian Army (under Lt-Col Agbabiaka) and elements of the 82 Division deployed from Enugu surrounded Odi and shelled the town with mortars. Ground troops then entered and, according to the subsequent Environmental Rights Action (ERA) and Civil Liberties Organisation reports, conducted house-to-house operations for ten days. Every building in Odi was destroyed except the Anglican church, the health centre and the bank. The town was looted and burnt.
Body-count estimates: the federal position is that 'a few militants' were killed; the ERA forensic survey returned 2,483 names with addresses; the most widely cited figure is 900+ confirmed dead, with 'thousands' displaced. In Gbomoru v Federal Republic of Nigeria (FHC/PH/CS/153/02), Justice Lambo Akanbi of the Federal High Court Port Harcourt awarded ₦37.6bn in compensation to the people of Odi against the FGN in 2013 — a judgment never paid in full and on which interest continues to accrue.
No soldier was ever prosecuted; Obasanjo defended the operation in his 2014 memoir My Watch. The Odi massacre is the founding atrocity of the modern Niger Delta insurgency: the Movement for the Emancipation of the Niger Delta (MEND) in 2005 traced its lineage explicitly to the Ijaw boys who survived Odi and went into the creeks. The unprocuted destruction of Odi authorised the equally undocumented destruction of Zaki Biam, Benue (October 2001, 300+ killed by Battalion 23 in retaliation for the killing of 19 soldiers), and the pattern was reproduced again at Baga, Borno (April 2013 and January 2015) and at Ibi/Wukari, Taraba (2019).