Story highlights Suicide bomber kills six people in Kano; Boko Haram suspected

Chibok is among at least three towns seized by fighters

Boko Haram fighters also overran two towns in Adamawa state, fleeing residents say

The militant Islamists "are all over the town firing heavy guns," one resident says

Boko Haram fighters late Thursday took over at least three towns in northeast Nigeria, including Chibok, the scene of the April kidnapping of more than 200 schoolgirls by the militant group, residents and a lawmaker said Friday.

"Boko Haram has taken over Chibok and we have all fled," said Enoch Mark, a Christian priest in the town whose daughter and niece are among the kidnapped girls. "They are now in control of the town, having overpowered the soldiers and the vigilantes."

The militant Islamist group also raided the towns of Hong and Gombi in Adamawa state, 100 kilometers (about 60 miles) from Yola, the state capital. Local hunters and vigilantes had pushed them out of Mubi, which lies near Nigeria's border with Cameroon and is the commercial hub of the state.

Boko Haram seized Mubi two weeks ago and renamed the town "Madinatul Islam" ("City of Islam" in Arabic). The militants began administering strict Sharia punishments, including public floggings and amputations.

With the invasion of the towns, the militants inched closer to Yola, where thousands of residents from areas seized by Boko Haram are taking refuge.

"Boko Haram are all over the town firing heavy guns as they patrol the streets," said Gombi resident Dahiru Sahabi. "They have burned down the police station, the local government secretariat and the market‎ after overpowering the police."

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Residents moved indoors or fled into the bush to escape the insurgents, said resident Rabi Tanimu‎.

"We are all indoors and all we hear is sounds of heavy guns and explosives," she said.

In Chibok, the town's vigilantes, who help provide security, were quickly overwhelmed by the firepower of the militants. One resident described Chibok as "a ghost town" as most residents fled the violence.

The insurgents had earlier raided the town of Hong, where they burned down a police station and hoisted their black flag outside the home of a retired military general, said fleeing residents.

Before attacking Hong, the ‎militants, riding in vans and on motorcycles, sacked a military checkpoint at nearby Marabar P‎ella village, where they converged after their ouster from Mubi and Maiha, said Hong resident Luka Buba.

Chibado Bobi, chief of staff in the Adamawa governor's office‎, confirmed that vigilantes and hunters had recaptured Mubi.

"The state government enlisted the help of the vigilantes and hunters to combat Boko Haram and it is paying off," Bobi said.‎

A resident of Mubi said Boko Haram militants fled the town in droves after the arrival of some 200 vigilantes and hunters, who were armed with homemade guns, spears, clubs, bows and arrows and machetes.

The resident, who asked not to be named for personal safety, said hunters captured the ousted occupiers' leader "outside the military barracks, which the militants (had) converted into their base."

Vigilantes reportedly reclaimed another town, Maiha, from Boko Haram on Wednesday after a fierce battle in which dozens of militants were killed.

The name "Boko Haram" translates to "Western education is sin" in the local Hausa language. The group has said its aim is to impose a stricter enforcement of Sharia law across Nigeria, which is split between a majority Muslim north and a mostly Christian south.

The fate of the schoolgirls abducted from Chibok remains unknown despite an announcement in October that Nigerian officials had reached a ceasefire deal with the group that included the girls' release.

Also Friday, a suicide bomber killed six people, including three police officers, and injured five others when he blew up his car at a gas station in northern Nigeria's largest city of Kano, police said.

The bomber, who police suspected to be a Boko Haram ‎terrorist, detonated the explosives concealed in his car as he lined up for fuel, Kano State Police Commissioner Adenrele Shinaba told reporters at the scene.