An attack by suspected radical militants from a group that was targeted by the United States in December airstrikes has killed 20 people in northwest Nigeria, an intel report showed on Sunday.

A confidential security report prepared for the United Nations seen by AFP said militants from the shadowy Lakurawa group raided the Fesken Rafi community in Kebbi state's Arewa district near the border with Niger, "killing more than 20 victims".

The raid reportedly occurred a few days ago, according to local media but was only reported over the weekend after the Kebbi state deputy governor visited the area. No exact date was given. AFP reached out to police and security officials for comment.

The attack happened after a lull in violence by Lakurawa in the past months, suggesting a resurgence of violence by the militant group, the report said, adding it may be intended to show its capability to stage complex operations in the face of intensified military offensives.

The US military struck parts of northwestern Nigeria on December 25, which the Nigerian government said targeted Islamic State group fighters, the Lakurawa militant group and "bandit" criminal gangs.

It is unknown how many were killed, and from which groups. But the United States claimed the strikes killed a large number of the militants, with Nigerian authorities claiming the militants had been "weakened" by military operations.

The motive of the latest attack was unclear.

'Transnational threat'

However, militants and criminal gangs of kidnappers and cattle thieves called bandits have in recent weeks been attacking and kidnapping farmers who fail to pay levies they impose on communities to allow them to cultivate their fields in northern and central Nigeria.

Lakurawa has remained active in communities along the Nigeria-Niger border despite efforts by security efforts for push them out.

The report warned that the Lakurawa violence could transform into a "transnational threat" due to the group's multinational composition, which complicates counterterrorism efforts.

Some researchers link Lakurawa to the Islamic State in the Sahel, which is primarily active in Mali and neighbouring Niger, although others remain sceptical.

The group which hailed from Mali, Niger and Burkina Faso crossed into Nigeria in 2018 established a presence in Kebbi and neighbouring Sokoto state in 2018 but became active in 2023, according to local officials.

It settled in Kebbi's Tsauni forest which straddles Niger. From their forest camps, they carry out deadly attacks, rustle livestock and impose tax on communities.

Last month, seven Nigerian troops were killed in an ambush by Lakurawa militants in nearby Sokoto state near the border with Niger, according to the military and local sources.

The militant insurgency in Nigeria, led primarily by Boko Haram and its rival faction, the Islamic State West Africa Province (ISWAP), has left tens of thousands dead and displaced millions since 2009.