Witnesses say the attackers rode motorcycles into villages in broad daylight and killed whoever they found.
The assailants appear to have been ethnic Fulani cattle herders who have a history of tension with local farmers.
Police say the attack is not linked to Islamist militant group Boko Haram, which is mainly active further east.
The militants are based in Borno state.
“The victims include men, women and children. Rescue teams are still combing nearby bushes [to] search for more bodies,” state police chief Hurdi Mohammed told the AFP news agency.
Nigerian newspapers describe the assailants as cattle rustlers.
Local MP Abdullahi Abbas Machika said 47 people were buried in one village alone in Katsina state after Wednesday’s attack.
Local residents have told the BBC Hausa service that security personnel have still not been deployed to the area.
President Goodluck Jonathan is currently visiting Katsina state to commission some government projects.
Mr Machika told the BBC that the security personnel were busy protecting the president while his constituents were being killed.