ABUJA, Nigeria — Islamic extremists killed nine people and injured four in Borno state in northeastern Nigeria, authorities said Sunday.

The attack was carried out by Boko Haram militants on the Malam Fatori community, Babagana Zulum, the state governor, said. He did not say when the attack happened.

The community, very close to the border of Chad, is about 167 miles from Maiduguri, Borno’s capital city.

The governor, represented by Sugun Mai Mele, the commissioner for local governments, warned residents against collaborating with militants.

“Anyone found collaborating with the insurgents to bring harm or attack to the people of Malam Fatori will be cursed,” he said, adding that there are measures being put in place to fortify the town against future attacks.

A resurgence of Boko Haram attacks has been shaking Nigeria’s northeast, as Islamic extremists have repeatedly overrun military outposts, mined roads with bombs and raided civilian communities, raising fears of a possible return to peak Boko Haram-era insecurity.

— The Associated Press