Nigerian troops killed over 300 members of kidnapping and cattle rustling gangs in the northwestern state of Zamfara this week, a state official said Friday.

Troops targeted the gangs in Gummi district in a two-day operation that "led to the elimination of more than 300 terrorists," Zamfara information commissioner Mahmud Muhammad Dantawasa said in a statement.

Jihadists and "bandit" gangs specializing in kidnapping for ransom terrorise communities in northern and central Nigeria, where they launch deadly raids and impose levies on farmers wishing to access their own fields.

Abubakar Muhammad, a Gummi resident, said soldiers and local vigilantes fought around 1,000 bandits who were relocating from their camp with hundreds of stolen herd late on Wednesday through Thursday.

"The soldiers and the vigilantes killed more than 300 bandits in the fight, which raged throughout the night and into the following morning,” Muhammad said.

Abubakar Kudi-Kasa, another resident, said the offensive began around 2130 GMT on Wednesday, with the sound of gunfire and explosions keeping the town awake throughout the night.

"The bandits are still under siege by soldiers and vigilantes," Kudi-Kasa said.

Troops tried to overrun the bandits' camp two weeks ago but were forced to withdraw due to the "sheer number of the well-armed bandits", Kudi-Kasa said.

"The soldiers prepared well and returned to hit them hard,” he added.

Another resident, Shehu Dandare, gave a similar death toll after troops "pounded" the gangs.

In July last year, Nigerian soldiers killed at least 150 bandits in an ambush on a massive convoy of around 350 bandits in nearby Kebbi state as they were heading to their camp in neighbouring Niger state, local officials said.

A month later, the military killed more than 100 bandits in Zamfara's Bukkuyum local government area, where fighter jets in coordination with ground troops pounded a gathering of more than 400 gang members in a forest camp, according to a security report prepared for the United Nations.

The Zamfara government described this week's operation as a "significant breakthrough" in the fight against violent crime.