ABUJA, Nigeria (AP) — Nigeria’s military killed 45 militants in the country’s northwest region, the Katsina state government said Saturday.

The clashes between the military and the gunmen happened on Friday in the Danmusa area of Katsina, the state’s Commissioner for Internal Security and Home Affairs Nasir Mua’zu said in a statement. It followed a failed attempt by the gunmen to steal cattle on Thursday.

“Seeking revenge, the bandits returned in large numbers on March 6,” Mua’zu said. “What followed was an intense and fierce battle. The army successfully neutralized all 45 bandits.”

Nigeria is battling a complex security crisis from different armed groups, especially in the north of the country. The United States has sent troops to the West African nation to help advise its military on the fight against insecurity.

Among the most prominent Islamic militant groups are Boko Haram and its breakaway faction, which is affiliated with the Islamic State group and known as Islamic State West Africa Province. There is also the IS-linked Lakurawa, as well as other “bandit” groups that specialize in kidnapping for ransom and illegal mining.

The crisis has worsened recently to include other militants from the neighboring Sahel region, including the Jama’at Nusrat al-Islam wal-Muslimin, which claimed its first attack on Nigerian soil last year.

Several thousand people in Nigeria have been killed, according to data from the United Nations. Analysts say not enough is being done by the government to protect its citizens.