BBC News with Sue Montgomery

The Nigerian President Goodluck Jonathan has declared a state of emergency in some parts of the country following a series of bomb attacks on Christmas Day. The Islamist group Boko Haram said it carried them out. President Jonathan has described the group as a "cancerous" growth attempting to destroy Nigeria. Tomi Oladipo reports from Lagos.

In a live address to the nation, President Goodluck Jonathan declared a state of emergency in some areas in the north of the country, which have become scenes of violence. The president also announced that the borders of these states would be closed to prevent what he described as terrorist elements from getting in. A special military unit will also be set upunder the chief of defence staff to overcome the security challenges. President Jonathan has been under increasing pressure to address the violence that has plagued many parts of northern Nigeria, and this announcement reveals his toughest stance so far.