Clashes between security forces and followers of a radical Islamic sect known as Boko Haram, or Taliban, broke out in northern Nigeria at the weekend, resulting in casualties and damage to buildings.
Police stations, prisons, churches and government institutions were attacked as the violence spread from Bauchi to other northern states.
Members of Boko Haram want Sharia law, already in force in northern Nigeria, imposed across the whole country.
Some people took refuge at police stations to escape the fighting. Residents were told to leave areas near the Boko Haram stronghold in Maiduguri as soldiers closed in.
After an all-out assault, security forces captured sect leader Mohammed Yusuf. He was later shot dead, but the precise cumstances of his death are unclear.
Hundreds of people are thought to have been killed in the clashes since Sunday, many of them in Maiduguri.
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