At least 12 people were killed, several wounded, and about 30 kidnapped in attacks by militants in northeastern and central Nigeria , police and officials said Monday.

Insecurity is a major concern in Nigeria, Africa's most populous country, where the country's new president is due to be sworn in next month following elections rejected by the opposition.

In the state of Adamawa, in the north-east of the country, unidentified gunmen stormed the town of Dabna, located in the Hung district, which "unfortunately led to the death of three (people)," according to local police spokesman Suleiman Nguroji, who also indicated that a number of houses were burned.

No one claimed responsibility for the attack, knowing that Boko Haram had previously launched attacks in the region from its stronghold, Sambisa Forest, in Borno state.

Also Monday, gunmen attacked residents of the Oganinigo district of Dekina district in central Kogi state, local authorities announced.

The governor's spokesman, Mohamed Onogwu, announced the death of a local politician and "others have been affected by this ugly and unfortunate attack."

On Sunday, gunmen stormed a church in the village of Akinawi-Tsoaref in central Benue State, killing one person and kidnapping three others, according to Salome Tor, a political official in Lugo County, in which the village is located.

"The attackers stormed the church during a morning service, killed one person and kidnapped three others, including the priest," Tor said.

Two people were seriously injured and taken to hospital for treatment, according to Tor. Tor did not name the party responsible for the attack, but Benio has been witnessing bloody violence for years between cattle herders and farmers.

In Niger state, located in the center of the country, gunmen suspected of belonging to criminal gangs attacked a number of villages in the provinces of Machigo and Monia, killing at least seven people and kidnapping 26 others, according to a local official.

Omar Jibrin Eguidi, a political official in Machigo County, said that the attacks are part of a series of attacks that have targeted villages in the region in the past two weeks, noting that a large number of residents have fled their homes.

Agence France-Presse was unable to obtain comment from the Niger state police on the attacks and kidnappings.

President Muhammadu Buhari's term ends in May, and Paula Tinubu will succeed him in the presidency of a country facing a jihadist rebellion in its northeast, gang violence in its northwest and center, and separatist movements in its southeast.