(CNN) -- Nigeria's president declared states of emergency Tuesday for three states, blaming "terrorists" aimed at "rebellion" who have caused "fear among our citizens and a near breakdown of law and order in parts of the country."
The order, issued by President Goodluck Jonathan, applies to Borno, Yobe and Adamawa states in northeastern Nigeria. He also noted a rise of insurgent violence in eight other states as well, including Nasarawa, where scores of police officers were killed last week.
"We have taken robust steps to unravel and address the root causes of these crises, but it would appear that there is a systematic effort by insurgents and terrorists to destabilize the Nigerian state and test our collective resolve," Jonathan said in a televised speech.
Insisting they weren't simply criminals, the president said "terrorist groups" were staging a "rebellion and insurgency" that threatened Nigeria's "unity and territorial integrity." Some northern parts of Borno state have already been taken over by such groups, as Jonathan noted.
Such violence over the years has been blamed on Boko Haram, whose name means "Western education is sacrilege." According to Human Rights Watch, the group has killed more than 2,800 people in an escalating campaign to impose strict Islamic law on largely Muslim northern Nigeria.
Attempts at dialogue -- which will continue, the president said -- have failed to curb militants' efforts "to progressively overwhelm the ... country." He cited several recent examples of violence, including the killing of "innocent civilians and state officials," attacks on government buildings and facilities and the destruction of Nigeria's flag for "strange flags" instead.
"These actions amount to a declaration of war and a deliberate attempt to undermine the authority of the Nigerian state and threaten her territorial integrity," Jonathan said. "As a responsible government, we will not tolerate this."
The president said he'll send more troops to the three states, adding that they and other security forces there have orders to "take all necessary action." They have the authority to detain suspects and those who illegally possess weapons, take over any building "used for terrorist purposes" and conduct searches.
"Those insurgents and terrorists who take delight in killing our security operatives -- whoever they may be, wherever they may go -- we will hunt them down, we will fish them out, and we will bring them to justice," Jonathan said.
"No matter what it takes, we will win this war against terror."