The Indigenous People of Biafra (IPOB) movement claimed in a statement that five of its members were killed when soldiers and police tried to kill its leader, Nnamdi Kanu, at his home in Umuahia.
The IPOB is demanding a separate state for the Igbo people who are the most populous ethnic group in Nigeria’s southeast. Fifty years ago, a declaration of Biafran independence sparked a brutal 30-month civil war.
The group’s spokesman, Emma Powerful, said that up to 30 others were injured.
Kanu’s lawyer, Ifeanyi Ejiofor, blamed President Muhammadu Buhari, who has previously condemned the IPOB leader. Kanu is currently on bail pending the resumption of his trial for treasonable felony in the capital, Abuja.
Army spokesman Major Oyegoke Gbadamosi described the IPOB claims as “fictitious” and said its account was “far from the truth”.
Suspected IPOB militants, he said, had blocked a convoy of military vehicles in Umuahia at about 6:00 pm (1700 GMT) and pelted troops with stones and broken bottles, injuring a soldier and a pedestrian.
“The troops fired warning shots in the air and the hoodlums dispersed. No life was lost,” he added in a statement.
There was no immediate independent verification of either account.
Amnesty International has previously claimed that Nigeria’s security forces killed at least 150 pro-Biafra protesters and injured hundreds more in the southeast since August 2015.
Separatist sentiment has persisted in the southeast despite defeat in the civil war and the huge loss of life.
Many believe successive federal governments have failed to invest in development and infrastructure in the region as a punishment for secession in 1967.
Kanu has called for “civil disobedience” to force a referendum on self-determination.
“We have chosen the track of peaceful agitation, non-violence, persuasion, logic, reason, argument,” he told AFP in an interview in May.
“We are going to deploy all of that to make sure we get Biafra.”
Tensions have been building since earlier this year, when Igbos living in the mainly Muslim north were told to go back to the largely Christian south by October 1.
At least two other groups in the south and southwest then revived their push for independence.
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