Nigeria's president on Saturday declared a state of emergency in parts of Africa's most populous nation, after a recent slew of deadly attacks blamed on a radical Muslim sect killed dozens of people.
President Goodluck Jonathan declared the state of emergency in four states and ordered the closure of international borders near the affected areas.
They include parts of northeastern state of Yobe, and the central states of Plateau and Niger, all hit by the Christmas Day attacks that left at least 42 people dead, for which a radical sect known as Boko Haram claimed responsibility. Attackers targeted churches and one of the state offices of Nigeria's secret police.
The president also declared a state of emergency in parts of the northeastern state of Borno, a stronghold of the feared Islamic sect.
"What began as sectarian crises in the northeastern parts of the country has gradually evolved into terrorist activities in different parts of the country with attendant negative consequences on our national security," Jonathan said.
Earlier in the year, an Aug. 26 bombing of the United Nations headquarters in Nigeria's capital Abuja killed 24 people and wounded 116 others. The sect claimed responsibility for that attack.
Jonathan also said Saturday that he has directed top security officials to set up a special counterterrorism unit to fight the growing threat posed by Boko Haram.
'Terrorism is a war against all of us'
The Christmas attacks come a year after a series of Christmas Eve bombings in central city of Jos in the nation's "middle belt," where the country's largely Muslim north meets its largely Christian south. Last year's Christmas attacks claimed by the militants left at least 32 dead and 74 wounded.
"Terrorism is a war against all of us," Jonathan said as he spoke during an address on national television on Saturday. "I call on all Nigerians to join hands with government to fight these terrorists."
The sect, some of whose members are believed to have links to al-Qaida, wants to impose Islamic Shariah law across Nigeria.
The U.S. Embassy had warned U.S. citizens late Friday to exercise caution in Nigeria.
"Violent extremist attacks have continued in various locations, including the states of Bauchi, Borno, Gombe, Kaduna, Kano, Niger, Plateau, and Yobe, resulting in numerous casualties," the warning read.
Boko Haram's widening terror attacks, though, are only further intensifying religious divisions in Nigeria. In this nation of more than 160 million people, thousands have died in recent years in communal fighting pitting machete-wielding neighbors against each other.
The sect came to national prominence in 2009, when its members rioted and burned police stations near its base of Maiduguri, a dusty northeastern city on the cusp of the Sahara Desert. Nigeria's military violently put down the attack, crushing the sect's mosque into shards as its leader was arrested and died in police custody. About 700 people died during the violence.
While initially targeting enemies via hit-and-run assassinations from the back of motorbikes after the 2009 riot, violence by Boko Haram now has a new sophistication and apparent planning that includes high-profile attacks with greater casualties. That has fueled speculation about the group's ties as it has splintered into at least three different factions, diplomats and security sources say. They say the more extreme wing of the sect maintains contact with terror groups in North Africa and Somalia.
Targeting the group has remained difficult, as sect members are scattered throughout northern Nigeria and nearby Cameroon, Chad and Niger.