Nigeria's president declares state of emergency
31 December 2011 Last updated at 16:49 GMT
Nigerian President Goodluck Jonathan has declared a state of emergency in areas worst hit by attacks by the Islamist group Boko Haram.
The measures will affect parts of four states in the north and east of the country, while borders will be closed temporarily in troubled areas.
Mr Jonathan vowed to "crush" Boko Haram, which killed dozens in attacks across the country on Christmas Day.