LAGOS, Nigeria — A French family kidnapped last week on the Cameroon-Nigeria border appeared on a video posted Monday on YouTube, with one of the hostages and a gunman saying that the family is being held by the Nigerian Islamist extremist group Boko Haram.
The family members — three adults and four children — are shown sitting on the ground inside a sort of tent made from prayer mats, in front of a black Qaeda-style banner, grim-faced but apparently in good health. The children, boys ages 5 to 12, fidget and glance at the camera. The family is flanked by two masked, fatigues-wearing men holding rifles, and in front of them s another masked hostage taker, who reads out a statement in Arabic demanding the release of “brothers” and “sisters” and threatening twice to “slaughter those we took” unless the group’s demands are met.
The French military campaign against Islamist militants in Mali is obliquely referred to by the masked gunman, who says “the president of France” has “waged war against Islam.”
Before that, a man identified by the French media as Tanguy Moulin-Fournier, the children’s father, reads a statement in French saying the family was “arrested” by Boko Haram. He uses the group’s Arabic name — it means “those engaged in the propagation and teaching of the prophet and of jihad” — which is responsible for hundreds of killings in a three-year insurgency in Nigeria’s north.
Next to him are a woman, apparently his wife, and a man, his brother; his wife is wearing a black head covering.
On Monday evening, French officials, including Prime Minister Jean-Marc Ayrault, identified the kidnappers as members of Boko Haram, with Foreign Minister Laurent Fabius calling the video “terribly shocking.”
But the link to Boko Haram remained unproven Monday night. The video differs from others released by the group in that Hausa, the language of Nigeria’s north, is not spoken on it, and Boko Haram had not previously been associated with kidnapping Westerners or showing them on videos. In addition, purported members of Boko Haram denied, in a statement to Nigerian journalists over the weekend, involvement in the kidnapping.
Mr. Moulin-Fournier, an expatriate employee of the French gas group GDF Suez, was vacationing with his family at a national park in northern Cameroon near the border with Nigeria when they were seized early last Tuesday by motorcycle-riding gunmen. Cameroon officials said the hostages were then taken across the border to Nigeria to the area that gave birth to Boko Haram nearly four years ago and where it is strongest, Borno State.
The group has waged a relentless guerrilla campaign of bombings and ambushes there and across northern Nigeria, which killed some 800 people last year alone. Its goals, beyond spreading mayhem and undermining the Nigerian state, remain vague, though it has demanded the establishment of Shariah law in Nigeria.
While Boko Haram claimed responsibility for the deadly 2011 bombing of the United Nations headquarters in Abuja, Nigeria’s capital, the group has focused mostly on Nigerian targets, which would make the kidnapping of the French family something of a departure. In the video, apart from the admonishment to “the president of France,” the masked gunman warns President Goodluck Jonathan of Nigeria that “we will establish the Islamic state of Nigeria.”
The gunman tells Mr. Jonathan in Arabic, according to the SITE Monitoring Service: “We say to you: If you want us to leave those French people, leave all of our women whom you imprisoned by your hands quickly, because we know that all ways of disbelief are the same, and all of you are equally in war with us.”
The gunman also warns the president of Cameroon to release Boko Haram members — the gunman uses that informal name for the group — though none is known to be held by that country.
Though kidnapping has not so far been part of Boko Haram’s campaign, it has figured in that of a splinter group, Ansaru, known to be holding a number of Western hostages.
Nigerian officials declined to comment on the video Monday night and have said almost nothing about the kidnapping. The French, however, reiterated their belief that the family is being held in Nigeria, not Cameroon.