The offensive was carried out in the northwestern Zamfara state where police on Saturday confirmed a mass kidnapping carried out earlier in the week.

Police there confirmed there had been a "mass" abduction of villagers in raids by armed gangs on Thursday night, but gave no figures.

Residents estimate that seven people had been killed and 150 abducted when large numbers of heavily armed men invaded six villages Bukkuyum local government area.

Police said a hunt has been launched for the attackers.

Sunday's security report said at "least 65 bandits" had been killed, in what it called a "major breakthrough".

But the "massive seven-hour ground and air offensive" was in Tsafe, a district around 200 kilometres (125 miles) from where the recent kidnappings occurred.

Zamfara is one of several states in northwest and central Nigeria plagued by the criminal gangs. Known locally as bandits, they carry out deadly raids on communities, kidnap residents for ransom and burn homes after looting them.

Bandit violence started more than decade ago as clashes between herders and farmers in conflict over limited water and land resources impacted by climate change.

The internecine violence morphed into organised cattle rustling and kidnapping for ransom syndicates.

Bandits motivated by financial gains are increasingly collaborating with jihadists from the northeast who have waged a 17-year-old armed insurrection for a Caliphate.