Police in Nigeria’s northwestern state of Zamfara have said they secured the release of 100 villagers kidnapped in early June following negotiations with their abductors.

Mohammed Shehu, spokesman for Zamfara state police, said in a statement on Tuesday the release was “unconditional” and that it had been secured “without giving any financial or material gain” to the gang.

The released hostages would undergo medical checks before being reunited with their families, Shehu said.

The group, including women and children, had been brought to a forest hideout after gunmen, locally known as bandits, stormed Manawa village on June 8.

A source familiar with the negotiations told the AFP news agency the bandits agreed to release the kidnapped villagers after the police and state authorities “assured them no action would be taken against them for the kidnap”.

Al Jazeera’s Ahmed Idris, reporting from the Nigerian capital Abuja, said that 24 other people were still to be evacuated from the forest due to their health condition as many were wounded.

The hostages’ release, without payment, could be explained by the government’s increased military activity in the area over the past few weeks, Idris noted, or the result of amnesty schemes granted to bandits in some states, such as in Katsina and Zamfara.

“But many Nigerians believe that that amnesty has not worked, and it’s not working, because many of them [bandits] that have abandoned arms, have taken them again against the state and continued their kidnapping,” Idris added.

Northwest and central Nigeria have in recent years fallen prey to gangs of cattle thieves and kidnappers who raid villages, killing and kidnapping residents in addition to stealing livestock after looting and burning homes.

The criminals have begun to focus on raiding schools and kidnapping students for ransom. Hostages are usually released after ransom payment, with those whose families fail to pay often being killed by the captors.

These groups operate from camps in the vast Rugu forest, which cuts across Zamfara, Katsina, and Kaduna states in Nigeria, as well as neighbouring Niger.

On Monday, 13 policemen were killed in Zamfara state when they were ambushed by a gang as they deployed to protect a village from imminent attack.

Nigeria’s air force has in the past attacked bandit camps while some northern states have sought to negotiate with the gangs by offering amnesties in return for disarmament. But both military deployment and attempted peace deals have failed to end the violence.

The air force said over the past two weeks, daily and nightly flights over Zamfara, Kaduna and Katsina states had “neutralised” hundreds of bandits.

On Sunday, intense gunfire from bandits caused a Nigerian fighter jet to crash in the northwestern state, but the pilot survived by ejecting from the aircraft.

Such gangs are not the only threat to the country’s northern region where armed group Boko Haram and its breakaway faction, the Islamic State West Africa Province (ISWAP), have also been carrying out attacks for years.

According to the United Nations, the armed groups have forced nearly 2.4 million people in Nigeria and neighbouring countries to flee.

Al Jazeera

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