An armed group posted a video on Monday showing what residents said were about 600 women, children and older people abducted in Friday's attack on a mosque in Dekara village.
The video, posted on Facebook and WhatsApp, showed large groups of people seated in a forested area surrounded by armed men. Several children could be heard crying in the background.
Reuters could not confirm the number of people abduced, but if confirmed it would rank among Nigeria's largest and most audacious mass kidnappings in recent years.
An official from Borgu district, where the attack happened, said 30 people had been killed during the attack and were buried on Sunday.
The official, who declined to be identified because she was not authorised to speak to the media, said villagers from the communities of Dakera, Gidan-Zana and Sabon Gida were affected.
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'We will defend our people'
In its first public comments on the incident, the presidency on Tuesday condemned the attack as cowardly and vowed that those responsible would be brought to justice.
"Terror will not cow Nigeria. We will defend our people, protect our communities and uphold the sanctity of human life," Tinubu said in a statement.
President Tinubu, who is seeking a second term office in elections next January, ordered security chiefs to provide regular updates on efforts to rescue those abducted and account for all those taken.
Abubakar Umar, the traditional head of Dakera community, said at least 2,000 people fled into neighbouring Benin following the attack.
Obed Nana, Niger state commissioner for information, told Reuters that authorities were still trying to verify the number of missing people.
"I don't want to be too speculative about it because you know how sensitive such information can be," Nana said.
Mass abductions for ransom have become common in parts of northwestern and north-central Nigeria, where heavily armed criminal gangs frequently raid villages, schools and highways.
(with newswires)



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