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IN DEPTH

  Profile: Boko Haram 
  Timeline: Tensions in Nigeria
  Nigeria's sectarian crisis
  Rights groups claim police killings

Reports of extrajudicial killings by Nigerian security forces circulated widely in the aftermath of clashes last year between the police and members of Boko Haram, a group that called for the enforcement of Islamic law, or sharia, across Nigeria.

Now Al Jazeera has obtained exclusive footage that appears to show Nigerian security forces ordering a number of people to lie in the road and then shooting them at close range.

Human rights groups allege that many of those killed following the clashes were unarmed civilians.

The footage obtained by Al Jazeera would appear to confirm those accusations.

Mike Hanna has this exclusive report.

Source: Al Jazeera