Abuja, Nigeria — Nigerian officials say seven Chinese nationals received medical attention Monday after being rescued from nearly six months in captivity. Nigerian military forces recovered the abductees in a weekend operation in the central state of Kaduna.

A spokesperson for the Nigerian Air Force, Gabriel Gabkwet, said in a statement Sunday that the Chinese nationals were rescued from the Kanfani Doka and Gwaska areas of Kaduna state after a tactical overnight operation.

He said the captors abandoned their enclaves, including the abductees and their weapons.

He said the abductees had been held for more than five months by terrorists who seized them from a mining site in the Shiroro local government area of Niger state.

Gabkwet did not immediately respond to calls for comment from VOA.

In a statement Monday, Niger state Governor Abubakar Sani Bello praised the air force for the rescue and said authorities will continue to collaborate with all security forces in the state to ensure citizens are safe and secure.

Officials said the rescued Chinese nationals were taken to an unidentified medical facility.

During the June attack at the mining site, at least 22 security operatives were killed, including police and the military.

Nigeria's central and northwestern states have seen increasing incidents of attacks by armed groups known as bandits.

On Monday, a local government spokesperson in the Kaura area of Kaduna state told Lagos-based Channels Television that armed men killed at least 37 people in an attack Sunday and burned down more than 100 houses.

Police have not commented on the development but security analyst Chidi Omeje blames the violence on the July escape of hundreds of inmates from the Abuja prison.

"When that jailbreak happened, and we were told that tens and tens of terrorists who were being held there escaped, where do you think they went to?" Omeje said. "We've not been told that they were rearrested, so they've now gone to reactivate their terrorist cells. So, it becomes very understandable if somebody begins to put two and two together."

For more than 13 years Nigeria has been battling Boko Haram and other insurgent groups in the country's northeastern region. An estimated 300,000 people have been killed in the crisis.

Authorities are also struggling to contain kidnap-for-ransom gangs active across other regions of the country.