Since 2009, an estimated 3,600 people have been killed in an insurgency launched by the group known as Boko Haram, which says it wants to establish an Islamic state in northeastern Nigeria.
Boko Haram has repeatedly attacked schools, churches, mosques and markets, but state institutions such as police stations and military facilities have remained primary targets.
Following a public outcry, the Nigerian government declared a state of emergency in three states in May this year and launched a military offensive against the group.
The Nigerian military claims to be making major strides in defeating Boko Haram, but rebel attacks continue. There is scant opportunity to verify military claims or investigate some of the human-rights abuses purportedly committed by the army.
Little is known about Boko Haram and its motivations, and information about the group's activities remains under a tight coil.
Al Jazeera explores the background of the armed group and examine how the crisis in the northeast is affecting Nigeria.
Origins of the group
The story of Boko Haram, or Jama'at ahl al-sunna li-da'wa wa-l-qital, as it is also known, is a difficult one to establish.
While Boko Haram is a religious organisation, it is almost impossible to separate the activities of the group with the political, economic and territorial struggles in northern Nigeria which, in spite of a secular consitution, is often divided on religious lines.
Established in 2002 in Maiduguri, Boko Haram spent 2002-2009 consolidating its base, spreading its disdain for Western education and government corruption, culminating in the creation of alternative schools and attacking symbols of state power, most commonly police stations in northern Nigeria.
The group purportedly changed tactics and attacks intensified after its leader, Mohammed Yusuf, was killed in police custody in 2009 following a police raid.
This resulted in reprisal attacks on police that spread to four states.
Since 2010 violence has intensified and on May 15, 2013 President Goodluck Jonathan was forced to declare a state of emergency in three of the states affected by Boko Haram.
The group believes that strict Islamic law should be imposed in Nigeria. Little is known about its leadership or members.
While Boko Haram has repeatedly targeted Christian institutions such as churches, most people killed in attacks have been Muslims.
Most of the children, women, men, and businesses affected are in the Muslim north, and many analysts say it is not a Christian-Muslim feud.
Some observers say the crisis stems from poverty and disenfranchisement of people in the northern region.They say people there feel abandoned by their leaders.
A large part of Nigeria's federal government budget is spent on security. Some Nigerians believe rogue elements within the security forces are behind some acts of violence, in order to profit from security contracts.
Since 2009, it is believed Boko Haram has merged into several different sub-groups:
- the core group: followers of Yusuf who want revenge and "justice" for his killing
- criminal gangs who use the name Boko Haram as a front for their crimes, carried out mainly for financial gain such as bank robbery
- individuals with political interests in seeing the Boko Haram crisis continue. Several high-profile Nigerian politicians have been linked to elements within the core group
- members of the Nigerian security services have also been accused of "fronting" as Boko Haram for financial gain
War on Western education
The English translation of Boko Haram is “Western education is sin”. Western education is central to the group's beliefs and activities.
Since the group started its offensive, it has followed the doctrine that Western education is haram - prohibited and against the teachings of Islam. Targeting schools has become a Boko Haram trademark.
This has resulted in thousands of parents across the region withdrawing their children from institutions where Western education is taught, fearing attacks.
In this way, Boko Haram has succeeded in creating an environment where children are taken out of class and schools are forced to shut down.
Following the declaration of a state of emergency, the security services set out to disconnect all communication, from mobile phones to satellite phones, making it difficult to contact people to verify what is happening on the ground.
The military have, on a day-to-day basis, put out information to the public giving the impression it is succeeding in the war against Boko Haram. It is difficult to cross-check the military's version of events, however.
The media have been seriously restricted from working in areas affected by the crisis. Al Jazeera, for instance, has been told in some cases that it cannot access these locations.
The military says it is for reporters' own safety, but there are doubts about this explanation. Some believe it is a calculated effort by the security services to make sure the war on Boko Haram is either not reported at all, or portrayed in a way that supports their side.
Al Jazeera has documented the plight of civilians caught up in the fighting, and that a refugee crisis has been created. All this has been done with extreme restrictions on movement imposed by the military.
A refugee crisis has come to fruition with thousands forced to move into neighbouring Cameroon and Niger. The UN estimates that up to 8,000 people have entered Cameroon alone, while local organisations say the number might be close to 20,000.
It is unclear how Nigeria’s Emergency National Management authorities are combating the crisis. It has said there's a lack of resources coming from the government.
A feeling exists among some people in the areas affected by Boko Haram that the authorities - and in particular the federal government - are not taking this crisis seriously.
The country's leadership, including President Jonathan, comes from the mainly Christian south. There is a perception that since the crisis is not affecting the area where the people in power come from, the leaders are not taking it seriously.
Risks to Nigeria
Nigeria is an incredibly resilent nation. It has experienced civil war, religious extremism, ethnic violence and several other crises since independence from Britain in 1960.
Some observers say the Boko Haram crisis could lead to civil war, or the country splitting up, but there is little evidence to back up these claims.
Unabated violence, a feeling of marginalisation by the federal government, unemployment and poverty however remain the primary seeds of discontent, and is likely to lead to more bloodshed in the country.
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