US President Donald Trump's threat to go into Nigeria guns-a-blazing to stop the killing of record numbers of Christians did not come out of the blue.
For months, campaigners and politicians in Washington have been alleging that Islamist militants were systematically targeting Christians in Nigeria.
But the BBC has found that some of the data being relied on to come to this conclusion are difficult to verify.
In September, popular television host and comedian Bill Maher upped the ante describing what was happening as a genocide.
Referring to the Boko Haram group, he said they have killed over 100,000 since 2009, they've burned 18,000 churches.
Similar figures have also been gaining traction on social media.
The government in Abuja has pushed back on these claims describing them as a gross misrepresentation of reality. It did not deny that there was deadly violence in the country. But officials said that terrorists attack all who reject their murderous ideology - Muslims, Christians and those of no faith alike.
Other groups monitoring political violence in Nigeria say the number of Christians who have been killed is far lower, and say most victims of the jihadist groups are Muslims.
Nigerian security analyst Christian Ani said that while Christians had been attacked as part of a broader strategy of creating terror, it was not possible to justify claims that Christians were deliberately being targeted.
And Nigeria is facing various security crises across the country, not just violence by jihadist groups, and these have different causes so should not be confused.
The country's 220 million people are roughly evenly split between followers of the two religions, with Muslims in the majority in the north, where most attacks take place.
What are US politicians saying?
Prominent Texas Senator Ted Cruz has been campaigning on the issue for some time and, highlighting similar figures to Maher on 7 October, he wrote on X that since 2009, over 50,000 Christians in Nigeria have been massacred, and over 18,000 churches and 2,000 Christian schools have been destroyed.
In an email to the BBC, his office made clear that, unlike Maher, the senator was not calling this a genocide but describing persecution.
Cruz accused Nigerian officials of ignoring and even facilitating the mass murder of Christians by Islamist jihadists. Trump, echoing these words, has described Nigeria as a disgraced country, saying the government continues to allow the killing of Christians.
The Nigerian government has denied this, saying it is doing its best to tackle the jihadists. Some officials have also welcomed the prospect of the US helping fight the insurgents, as long as it is not done unilaterally.
The authorities have certainly struggled to contain the violent jihadist groups and criminal networks – most weeks seem to come with stories of fresh attacks or abductions.
Boko Haram – infamous for kidnapping the Chibok girls just over a decade ago - has been active since 2009, but its activities have been concentrated in the north-east, which has a majority Muslim population. Other jihadist groups have also emerged, including the Islamic State West Africa Province but they also operate in the north-east.
The figures for Christian deaths cited by some in the US are alarming, but assessing their accuracy is hard.
Where do their numbers come from?
When it comes to the source of the data, on a podcast in September, Cruz directly referred to a 2023 report by the International Society for Civil Liberties and Rule of Law (InterSociety) - a non-governmental organisation that monitors and tracks human rights abuses across Nigeria. His office also sent the BBC a number of links to online articles on the issue – most of which pointed back to InterSociety.
Maher did not respond to a BBC request for the source of his figures, but given certain similarities to those used by Cruz, it seems likely that he was drawing on InterSociety's work.
For data that could be shaping US policy towards Nigeria, InterSociety's work is opaque.
In its report published in August, which was an amalgamation of previous research and updated numbers for 2025, it said jihadist groups in Nigeria had killed over 100,000 Christians in the 16 years since 2009.
It also notes that 60,000 moderate Muslims also died during this period.
InterSociety did not share an itemised list of sources, making it hard to verify the total number of deaths it reports.
In response to this criticism, the organisation has said that it is almost impossible to reproduce all our reports and their references dating back to 2010. Our easy method is to pick their summary statistics and add them to our fresh discoveries or findings to make up our new reports. But the data sources quoted by InterSociety in its reports do not reflect the figures published.
What about those killed in 2025?
Looking at deaths this year alone, InterSociety concluded that between January and August just over 7,000 Christians were killed. This is another figure that has been widely shared on social media, including by Republican Congressman Riley M Moore, who has been a leading voice on this issue in the House of Representatives.
InterSociety includes a list of 70 media reports as some of the sources to its findings on the attacks against Christians in 2025. But in about half of these cases, the original news stories did not mention the religious identity of the victims.
For example, InterSociety quoted an Al Jazeera report of an attack in north-eastern Nigeria, saying that according to the news organisation not less than 40 farmers mainly Christians were abducted by Boko Haram in Damboa part of Borno State. But Al Jazeera's report didn't mention that the victims were mainly Christians, as quoted by InterSociety.
InterSociety told the BBC that it does further analysis to identify their background, without explaining how exactly in this case, but did mention their knowledge of local populations and use of Christian media reports.
Adding the number of death referenced in these reports cited by InterSociety does not result in the stated total of 7,000. The BBC added up the number of deaths from the 70 reports and found that the total was around 3,000 deaths. Some of the attacks also appear to be reported more than once.
To explain the shortfall, InterSociety says it also estimates the number of people it believes have died in captivity and includes eyewitness testimonies it cannot make public.
Who is behind the killings?
Included in its list of perpetrators are Islamist militant groups like Boko Haram but also Fulani herders. The Fulanis are a mainly Muslim ethnic group who live across West Africa and have traditionally earned their living by raising cattle and sheep.
The inclusion of the Fulani herders, who InterSociety describes as jihadists in all its reports, however, is the source of some controversy in Nigeria over how these killings should be categorised.
While the herders tend to be Muslim, many researchers in this field reject the description of this as a religious conflict, saying it is often about access to land and water.
Fulani herders have come into conflict with both Muslim and Christian communities across Nigeria.
Security analyst Mr Ani argues that to say that they are jihadists - it's a far stretch. It has nothing to do with that. It has a lot more to do with rogue and criminal elements.
Confidence McHarry, a senior security analyst at Africa-focussed consultancy SBM Intelligence, says the clashes are often due to ethnic tensions and competition over resources.
It might be ethnic in nature - they're seeking to grab lands, they're seeking to expand territory, but the more they displace communities and the more they attack worship centres, the more these things tend to get looked at in that light.
InterSociety also mention what are known in Nigeria as bandits, saying they are mostly ethnic Fulanis in the north-west of the country, who are involved in kidnapping and have a track record of killing both Christians and Muslims.
What about Trump's figures?
In a Truth Social post last Friday, Trump cited a figure of 3,100 Christians killed. He was referring to a report by Open Doors for deaths for the 12 months from October 2023, a White House official said.
Open Doors is a charity which researches the persecution of Christians worldwide.
In its reporting it says that while 3,100 Christians died, 2,320 Muslims were also killed in that 12-month period.
Open Doors also includes what it calls Fulani Terror Groups in its list of perpetrators and says they were responsible for almost a third of Christians killed during those 12 months.
Frans Veerman, senior research fellow at Open Doors, said what we see now is that Christians are still targeted, but increasingly some Muslims are targeted by Fulani militants.
Analysts say there are many violent attacks on mosques and Muslim communities in the north-west of the country.
One could say that this is part of the broader insecurity, said Mr McHarry. The reason why it is not assumed to have a religious dimension is down to the fact that the identities of the people who are carrying out these attacks against Muslims are themselves Muslims.
