Nigeria’s military has rejected claims by Boko Haram that it has imposed Shariah law in Nigeria’s northeast. The militant group has been trying to establish an Islamic caliphate in the country since 2009.

Abubakar Shekau, Boko Haram's leader, had said Sunday that the group had taken control of Gwoza, which lies about 528 miles northeast of Nigeria’s capital Abuja. Shekhau congratulated his fighters, in a video released by the group, and announced that it has set up an Islamic state in parts of northeastern Nigeria, BBC reported. The group, whose name means "Western education is sinful," also raised its flags over the palace of the Emir of Gwoza, the town's traditional ruler, the report added, citing local residents.

“The claim is empty,” Nigeria’s Defense Headquarters said on its Twitter account late Sunday, according to Bloomberg, adding: “The sovereignty and territorial integrity of the Nigerian state is still intact.”

“Any group of terrorists laying claim to any portion of the country will not be allowed to get away with the expression of delusion and crime,” the Defense Headquarters said, according to Bloomberg, adding: “Appropriate military operations to secure that area from the activities of the bandits is still ongoing.”

Despite the Nigerian military's rejection of Boko Haram’s statements, Shekhau said in the video that the group was now equipped with arms and ammunition from the Nigerian military, and said that it would continue more attacks. The fighting between government forces and the Islamist group has displaced more than 400,000 people so far. 

“Allah has granted us victory in the town of Gwoza, not because of our might but because we are committed to do his work,” Shekau said in the video, according to All Africa, a local news agency, adding: "We are grateful to Allah for the big victory he granted our members in Gwoza and made the town part of our Islamic caliphate.”

Last week, a group of soldiers fighting for the Nigerian government, refused to fight Boko Haram until they are better equipped. Earlier this month, Amnesty International also accused the Nigerian military and its civilian militia of committing serious human rights violations.