A government inquiry later found that, while long-standing tensions existed between Boko Haram and the Nigerian Security forces, the immediate cause of the violence stemmed from an incident in which a group of the sect's members were stopped by police in the city of Maiduguri as they were on the way to the cemetery to bury a comrade. The officers, part of a special operation aimed at stamping out violence and rampant crime in Borno State, demanded that the young men comply with a law requiring motorcycle passengers to wear helmets. They refused and, in the confrontation that followed, several were shot and wounded by police.