Nigerian military abuses were responsible for the deaths of some 8,000 people in its fight against Boko Haram extremists said a report by Amnesty International released Wednesday, which names senior officers that should be investigated for alleged war crimes.

The scathing report from the London-based human rights group called on Nigeria's newly-elected government, led by former military dictator Muhammadu Buhari, to urgently investigate the deaths of "8,000 people murdered, starved, suffocated, and tortured to death."

There was no immediate response from the military or Buhari, who was traveling to Niger in his first trip abroad since his election.

Boko Haram has been fighting to impose Islamic Law across Nigeria's north for the last six years, massacring civilians and kidnapping thousands of women and children, but Amnesty alleges that the military's response has resulted in further atrocities against civilians.

During their campaign against Boko Haram, the Nigerian military detained more than 20,000 people — often on scant evidence — and then held them in brutal conditions that resulted in many deaths, alleged the report.

The report said three major generals and two brigadier generals should be charged with war crimes and called for the government to end the impunity that has protected its military. It has also said four top military leaders, including the current army and defense chiefs of staff, should also be held responsible.

Amnesty said it interviewed 412 people over several years for the report, including victims, relatives, witnesses and activists as well as doctors and military officials.