U.N.: Nigeria's Islamists Could Face War Crimes Charges

Nigeria's Boko Haram Islamists could face charges of crimes against humanity, the U.N.'s human rights office warned Friday, also urging the government to ensure civilians are not swept up in an army counter-offensive.

"Members of Boko Haram and other groups and entities, if judged to have committed widespread or systematic attacks against a civilian population -- including on grounds such as religion or ethnicity -- could be found guilty of crimes against humanity," said Rupert Colville, spokesman for the U.N. High Commissioner for Human Rights.

"Deliberate acts leading to population 'cleansing' on grounds of religion or ethnicity could also amount to a crime against humanity," he told reporters.

Nigeria's military has launched an offensive against Boko Haram strongholds, after President Goodluck Jonathan imposed a state of emergency in three northeastern states following the Islamists' seizure of territory and declaration of war on the government.

Colville underlined that U.N. rights chief Navi Pillay had repeatedly slammed the "cowardly attacks" by Boko Haram against civilians, politicians, the security forces and foreign nationals.

But with Nigeria's military accused of massive rights violations in the past, including indiscriminate attacks on the ordinary population, there are warnings of a risk of high number of civilian deaths.

"We also call on the Nigerian government to make sure its efforts to achieve security are in full compliance with human rights principles," said Colville.

"We urge security forces and the military to respect human rights, and avoid excessive use of force when conducting operations, as these can all too easily feed local resentment, especially when civilians are killed or have their property damaged," he added.

Boko Haram has become notorious for blending in with the local population, both in towns and major cities where they have carried out suicide bombings as well as gun and bomb assaults.

The conflict is estimated to have cost 3,600 lives since 2009, including killings by the security forces.