(CNN) -- Until the abduction of more than 200 girls at the Government Girls Secondary School in rural Chibok, Nigeria's Boko Haram insurgency received scant attention in the global media, which gave it brief airtime when the insurgents exploded their bombs or torched a school. However, the mass abduction has brought the world's attention to the callous and unceasing violence that has become routine in northern Nigeria over the last three years. The area has suffered more than three decades of religious violence between Muslims and Christians. But since Boko Haram founder Mohammed Yusuf was killed in a 2009 security crackdown -- along with hundreds of his followers -- the militant Islamist group has stepped up its attacks.
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Global media paid Boko Haram little attention until 200 girls were abducted, says Shehu Sani
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Boko Haram became more violent after its founder was killed in 2009, he says
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At talks in 2011, the group blamed government action for their militancy, Sani says
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He says the use of force to free hostages can be deadly and negotiations must be held
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