Ali Hassan should be happy to return to Gwoza, his hometown, following the news on Friday that it had been retaken from the jihadist group Boko Haram by the Nigerian military. But Hassan remains unfazed.

Like many displaced persons taking refuge in Maiduguri, the Borno state capital, Hassan is not convinced that the military is being entirely truthful about its claims.

“I know fighting has been taking place but I don’t want to believe we’ve heard the last of it,” he said. “Boko Haram has a strong base in Gwoza, and it wouldn’t be easy dislodging them. They have large camps, thousands of fighters, heavy weapons and their headquarters there. The war in Gwoza wouldn’t be child’s play.”

Hassan isn’t the only one skeptical about the supposed victory.

An unnamed soldier told a local news website that fighting was still going on, even as the Nigeria Defense Headquarters announced Gwoza’s recapture from Boko Haram on Twitter.

The soldier was quoted as saying: “The announcement was made because my bosses are trying to please Mr. President, who announced that the town would be liberated by today.”

On Wednesday, as he received international election monitoring groups, Nigerian President Goodluck Jonathan said the military command had assured him that Gwoza would be liberated on Friday.

Nigeria’s presidential election is currently ongoing.

Jonathan is being challenged by Muhammadu Buhari, a former military general who is vying to become the first candidate to beat an incumbent in Nigeria’s history. Buhari has argued that Jonathan didn’t put enough effort into fighting the Boko Haram insurgency earlier. For his part, Jonathan has said he is determined to beat the militants. Polls have the two men in a dead heat.

The military says that Boko Haram insurgents have now been driven from virtually all the territory they’ve previously held, a claim that supports Jonathan’s assertion that Boko Haram is on the run.

The move on Gwoza followed the liberation of more than 30 other towns in the northeast in recent weeks. Boko Haram seized the town in August of last year, declaring that they were ruling it by Islamic law. The insurgents are believed to have held some 200 schoolgirls, kidnapped from Chibok almost a year ago, in the town.

Nigerian military spokesman Major-General Chris Olukolade said it wasn’t clear if the abducted schoolgirls were in the seized town.

“A massive cordon and search has commenced to locate any of the fleeing terrorists or hostages in their custody,” he said on Friday.

The capture of Gwoza is a major milestone for the Nigerian army and surely deals a huge blow to Boko Haram.

Gwoza's location made it an ideal base for the insurgents—the nearby Mandara Mountains offered protection and the jihadists could flee into Cameroon with ease. There is a complex system of caves and tunnels nearby, some of which burrow hundreds of meters into the mountainside. Many believe that Boko Haram’s leader, Abubakar Shekau, may have been hiding in those caves.

When Gwoza was captured by the jihadists last August, thousands of residents were left trapped and terrified on the mountain slopes with no food. To make matters worse, the military fled, leaving the militants to help themselves to the local armory.

But on Friday, the military said troops leveled the operational headquarters of Boko Haram and seized several arms and ammunition from them, forcing many insurgents to flee.

Eyewitnesses say that after the military assault, militants could be seen heading over the mountain by torchlight.

Though the recent success of multinational forces over Boko Haram brings huge relief to Nigeria’s troubled northeastern region, some are worried the gains might not be sustained.

Chad’s President Idriss Deby, who has been fiercely critical of Nigeria's response, said the Nigerian military had been uncooperative.

He told French magazine Le Point that Chadian troops have had to retake towns twice from Boko Haram because Nigeria’s forces had failed to secure them.

“The Chadian army is fighting alone in its part of the Nigerian interior and that is a problem. We have had to retake certain towns twice,” Deby was quoted as saying.

“We are forced to abandon them and Boko Haram returns, and we have to go back. That has a human and material cost.”