AMSTERDAM -- The prosecutor of the International Criminal Court says that after a preliminary investigation she believes that acts attributed to the Nigerian Islamist group Boko Haram are likely crimes against humanity.
"Information available provides a reasonable basis to believe that since July 2009 Boko Haram has launched a widespread and systematic attack that has resulted in the killing of more than 1,200 Christian and Muslim civilians in different locations throughout Nigeria," Fatou Bensouda wrote in a report issued Monday.
She said the potential crimes against humanity include murder and persecution. But she said she will only move to a full-fledged investigation after further study and depending on whether Nigerian authorities themselves are willing and able to prosecute "those who appear to bear the greatest responsibility."
Her report was based on evidence gathered through December 2012.
Nigeria declared a state of emergency on May 14 to fight an Islamic uprising by militants in the northeast who want to impose Islamic law across a country divided almost equally between the predominantly Muslim north and mainly Christian south.
Boko Haram's center of power is in the northeast, but last month Nigeria's army arrested 42 suspected Islamic extremists in the southwest states of Lagos and neighboring Ogun.
Bensouda noted that while that Nigerian government forces may also have violated human rights while conducting operations against Boko Haram, as of December 2012 there was no evidence they were targeting civilians.
The International Criminal Court is the world's permanent war crimes court, established in The Hague, Netherlands in 2002. The prosecutor's office formally launched its investigation into the situation in Nigeria in November 2010.
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