By Felix Onuah
ABUJA, Aug 4 (Reuters) - Nigerian President Umaru Yar’Adua said on Tuesday he had ordered an investigation into the killing of the leader of an Islamic sect behind a five-day uprising which killed close to 800 people.
Mohammed Yusuf, 39, a radical cleric and leader of the militant Boko Haram sect, was shot dead in police custody last Thursday as the security forces fought to end days of bloody rioting by his followers.
"Yesterday, I ordered the national security advisor to carry out a post mortem with the security agencies as a first step so we can have a full report, including how the leader of Boko Haram was killed, the circumstances under which he was killed," Yar’Adua said.
He described Yusuf’s killing in the northern city of Maiduguri as a "very serious issue" and said the authorities would decide whether to carry out further investigations once the report was complete.
"I have been emphasising since this administration came to power our uncompromisable stance on the rule of law and everybody in this country, and all the officials, are aware clearly and unambiguously of the stance," he told reporters in the capital Abuja.
A Reuters reporter and other local journalists saw Yusuf last Thursday, standing and with no obvious serious injuries, at a barracks in Maiduguri after his capture.
He was then transferred to police headquarters where he was killed several hours later.
Officials have said he died in a shoot-out while trying to escape, but rights groups have condemned what appeared to have been an execution-style killing.
His bullet-riddled body was laid in front of the police headquarters the next day for members of the public to view.
Human Rights Watch said Yusuf’s killing displayed "brazen contempt by the Nigerian police for the rule of law".
Amnesty International has also called for an investigation.
Followers of Boko Haram, which means "Western education is sinful", attacked government buildings, police stations, prisons, schools and churches during five days of rioting before soldiers and police put the uprising down.
The bodies of scores of suspected Boko Haram followers were displayed alongside that of Yusuf as part of a military "show of force" meant to reassure the public that the situation had been brought under control.
The sect, which wants to see a stricter enforcement of sharia (Islamic law) across Africa’s most populous nation, is loosely modelled on the Taliban in Afghanistan.
Yar’Adua said during the uprising the group was procuring arms and learning to make bombs in order to impose its ideology on Nigerians by force. Two days before Yusuf was killed, he met with security chiefs and promised an operation that would "contain them once and for all". (Writing by Nick Tattersall; Editing by Sophie Hares)