When the United States ordered airstrikes on Christmas Day against Islamist militants in northern Nigeria, officials in Washington said the action was aimed at protecting Christians facing threats of violence.
The strikes thrust Nigeria's long-running sectarian bloodshed into the global spotlight - and revived claims that a "Christian genocide" is unfolding in Africa's most populous country.
But in an interview, the UN's top humanitarian official in the country has told UN News that the current crisis extends far beyond any single community or conflict. Violence, he cautioned, has spread across much of the country, leaving millions displaced and fuelling what aid agencies describe as one of Africa's largest - and most overlooked - humanitarian emergencies.
"Security remains one of Nigeria's major challenges," said Mohamed Malik Fall, the UN resident and humanitarian coordinator. "You can no longer associate it with a single region. It is almost everywhere."
A conflict that spread
The crisis began in the northeast in 2009, with an insurgency led by the jihadist group Boko Haram, later joined by splinter factions, including the Islamic State-West Africa (ISIS-WA).
Nearly two decades in, the violence has reshaped large parts of the country.
More than two million people remain displaced in the northeast alone, many of them for years. "An entire generation has grown up in displacement camps, knowing nothing else," Mr. Fall said.
The human toll is extensive: more than 40,000 people killed since the start of the insurgency, thousands of schools and health centres destroyed, and vast agricultural areas rendered inaccessible. But Mr. Fall said the deeper damage has been economic and social.
"People have been cut off from all economic activity," he said. "They are deprived of the ability to live from their work and preserve their dignity."
Untargeted violence
What was once a localized insurgency has morphed into something broader and more diffuse.
In Nigeria's northwest - in states such as Zamfara, Katsina and Sokoto - armed criminal groups have seized control of rural areas, carrying out mass kidnappings and extortion, a phenomenon authorities describe as banditry.
Entire villages have been abandoned, and around one million people are now displaced in the region, according to United Nations estimates.
In the country's central belt, clashes between farmers and herders over land, intensified by climate pressure and environmental degradation, have triggered further displacement.
Elsewhere, separatist movements and attacks linked to oil production continue to destabilize communities.
The cumulative result is a country with roughly 3.5 million internally displaced people - nearly 10 percent of all displacement across Africa.
A loaded claim
Recent attacks against churches and Christian schools have revived international attention. In January, more than 160 worshippers were abducted during Sunday services in Kaduna State.
Days earlier, villages in the northwest were attacked, killing dozens, while students near a Catholic school in Papiri were again targeted.
The violence revived memories of the 2014 abduction of 276 schoolgirls from Chibok , most of them Christian, by Boko Haram - a moment that once galvanized global outrage.
Citing the need to protect Christians from Islamist militants, the US administration ordered airstrikes on Christmas Day against jihadist positions in northern Nigeria. In Washington, some officials have since argued that a "Christian genocide" is underway.
The UN is refraining from that characterisation.
"Attributing this violence to the targeted persecution of a religious group - I would not take that step," Mr. Fall said. "The vast majority of the more than 40,000 people killed in the insurgency are Muslims. They were attacked and killed in mosques."
He pointed to an attack in Maiduguri, the historic centre of the insurgency, carried out on Christmas Eve in an area "between a mosque and a market," which killed Muslim worshippers as they left prayers.
"Insecurity affects everyone, without distinction of religion or ethnicity," he said, warning that oversimplified narratives risk deepening social fractures rather than addressing their causes.
A crisis measured in millions
Behind the violence lies a humanitarian emergency of enormous scale. In the northeastern states alone, 7.2 million people need assistance - nearly six million of them in severe or critical condition, according to U.N. figures.
Food insecurity has become the defining threat. Aid agencies project that up to 36 million Nigerians could face varying levels of food insecurity in the coming months. Among children under five, more than 3.5 million are at risk of acute malnutrition.
"The consequences are not only immediate," Mr. Fall said. "Malnutrition affects cognitive development, education, and continues to shape lives well into adulthood."
Climate shocks - including droughts and floods - have compounded the crisis, alongside recurring cholera and meningitis outbreaks and a fragile health system.
Aid shrinks as needs grow
Despite the scale of the emergency, funding has collapsed.
"A few years ago, Nigeria's humanitarian response plan raised close to $1 billion annually," Mr. Fall said. "In 2024, it was $585 million. Last year, barely $262 million. This year, we are not even certain we will reach $200 million."
The decline comes as donor attention has shifted to higher-profile crises elsewhere, including Ukraine and Sudan.
A test for Africa's largest economy
Nigeria's predicament exposes a stark paradox: one of Africa's largest economies confronting a humanitarian crisis more often associated with far poorer states.
"Nigeria is not Sudan. It is not Somalia. It is not South Sudan," Mr. Fall said. "This is a country with resources. The primary responsibility for responding to humanitarian needs lies with the government."
The UN is now urging Nigerian federal and state authorities to take greater ownership of the response, even as it presses donors not to turn away.
"No one wants to live on aid," Mr. Fall said. "People would rather be helped to access economic opportunities than remain dependent. Giving a fish is good. Teaching how to fish is better."
