Ethiopian security forces killed over 400 people last November when the Oromo community protested against government plans to expand the territory of Addis Ababa, says Human Rights Watch in its report released on Thursday.

The 61-page report; Such a Brutal Crackdown’: Killings and Arrests in Response to Ethiopia’s Oromo Protests, details the Ethiopian government’s use of excessive and unnecessary lethal force and mass arrests, mistreatment in detention, and restrictions on access to information to quash the protest movement.

Human Rights Watch interviews in Ethiopia and abroad with more than 125 protesters, bystanders, and victims of abuse documented serious violations of the rights to free expression and peaceful assembly by security forces against protesters and others from the beginning of the protests in November 2015 through May 2016.

The organization is urging the Ethiopian government to urgently support a credible, independent investigation into the killings, arbitrary arrests, and other abuses.

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“Ethiopian security forces have fired on and killed hundreds of students, farmers, and other peaceful protesters with blatant disregard for human life,” said Leslie Lefkow, deputy Africa director at Human Rights Watch.

Mr Lefkow said the government should immediately free those wrongfully detained, support a credible, independent investigation, and hold security force members accountable for abuses. Human Rights Watch and other organizations have identified more than 300 of those killed by name and, in some cases, with photos.

Proposed expansion of the capital

The November protests were triggered by concerns about the government’s proposed expansion of the capital’s municipal boundary through the Addis Ababa Integrated Development Master Plan.

Protesters feared that the Master Plan would displace Oromo farmers, as has increasingly occurred over the past decade, resulting in a negative impact on farm communities while benefiting a small elite.

The report says investigations found that security forces used live ammunition for crowd control repeatedly, killing one or more protesters at many of the hundreds of protests over several months.

Witnesses described the scale of the arrests as unprecedented. The report quotes Yoseph, 52, from the Wollega zone, saying; “I’ve lived here for my whole life, and I’ve never seen such a brutal crackdown. There are regular arrests and killings of our people, but every family here has had at least one child arrested.”

Former detainees told Human Rights Watch that they were tortured or mistreated in detention, including in military camps, and several women alleged they were raped or sexually assaulted. Some said they were hung by their ankles and beaten; others described having electric shocks applied to their feet, or weights tied to their testicles.

However, there have been some credible reports of violence by protesters, including the destruction of foreign-owned farms, looting of government buildings, and other destruction of government property. But the Human Rights Watch investigations into 62 of the more than 500 protests since November found that most have been peaceful.