The Nigeria Army has condemned an Amnesty report saying Nigeria’s security forces have killed more than 150 peaceful protesters since August 2015.
Amnesty International said the country’s military used live ammunition and deadly force against pro-Biafra protesters who were campaigning for independence from Nigeria.
Nigeria’s police denies allegations that it used unnecessary force.
The country’s army said Amnesty was trying to tarnish its reputation.
Amnesty’s report is based on interviews with almost 200 people, alongside more than 100 photographs and 87 videos.
Among the allegations contained in the report are what Amnesty called “extrajudicial executions”, when 60 people were shot and killed in Onitsha, in the two days surrounding Biafra Remembrance Day in May 2016.
“This reckless and trigger-happy approach to crowd control has caused at least 150 deaths, and we fear the actual total might be far higher” said Makmid Kamara, Amnesty’s interim director for Nigeria.
Other victims detailed in the report include a 26-year-old man who was shot in Nkpor, but hid in a gutter, still alive. He said when soldiers found him, they poured acid over him, and told him he would die slowly.
Another woman said she had been speaking to her husband on a mobile phone when he told her he had been shot in the abdomen. He was calling from a military vehicle, she said, and she heard gunshots. She later found his body in a morgue with two more wounds in his chest, leading her to believe he had been executed after the call.
The human rights organisation said pro-Biafra protests had been “largely peaceful” despite occasional incidents of protesters throwing stones and burning tyres – and one occasion when someone shot at police.
“Regardless, these acts of violence and disorder did not justify the level of force used against the whole assembly.”
But army spokesman Sani Usman that “the military and other security agencies exercised maximum restraints despite the flurry of provocative and unjustifiable violence”.