Nigerian security forces in Zamfara last week began one of their largest recent operations against the armed gangs, known locally as bandits, in an attempt to halt the surge in violence.

Looking to disrupt the armed groups' communications, the country's telecoms regulator also ordered operators to shut their towers in Zamfara as the military began raids and air strikes on bandit hideouts.

A security aide to Katsina State Governor Aminu Bello Masari said telecommunication services were now also shut in 13 of that state's 34 districts on the border with Zamfara.

"The shutdown is meant to stop bandits from Zamfara moving into Katsina state to use telecom services for their terrorist activities," Ibrahim Ahmed Katsina said.

"For now the shutdown affects 13 local governments to aid ongoing security operations but we will not hesitate to expand the shutdown where necessary," Katsina said.

Northwest and central Nigeria have long been plagued by criminals gangs who raid communities, stealing cattle and kidnapping residents for ransom after looting and burning homes.

But the violence has escalated this year and bandits have turned their sights on schools and colleges to abduct hundreds of pupils in a series of mass kidnappings.

Heavily-guarded bandit camps dot the Rugu forest that straddles the northern states of Kaduna, Katsina Zamfara and Niger.

Hundreds of troops aided by gunships and fighter jets launched offensives on Saturday on bandits camps in the Shinkafi area of Zamfara state, security sources have said.

Following the telecoms shutdown Zamfara residents have been trooping to Funtua in Katsina state to make phone calls and bank transactions, which have also been disrupted.

Local officials and residents say gangs of bandits fleeing the military offensive have attacked communities in neighbouring states.

Gunmen presumed to be from Zamfara kidnapped more than 20 people on Wednesday in a village on the provincial border in neighbouring Sokoto State, police said.

On Thursday six people were killed and seven more kidnapped in a pre-dawn raid by bandits on Tureta town in Sokoto, Muhammad Sadiq Abubakar, the state's police spokesman told AFP.

On Wednesday locals in Bakori town in Katsina state arrested a bandit fleeing with his family from Zamfara, according to local residents.

Past military campaigns and amnesty deals with bandits sought by local governors have failed to end the attacks.

Under pressure over worsening insecurity in Nigeria, President Muhammadu Buhari has ordered security chiefs to find urgent ways to curb violence in the northwest even as they battle a 12-year jihadist insurgency in the country's northeast.