SOLDIERS sit sweltering in bunkers made from sandbags on the streets of Maiduguri, a town in north-eastern Nigeria at the centre of a four-year Islamist revolt. Around them, young boys on clanking bicycles carve through sand blown in from the Sahara, which has been slowly burying a town that was once, long ago, a thriving Islamic trading centre. It now faces desertification, literal and figurative.

This month Nigeria’s army launched its most determined effort yet to crush Boko Haram, a terror group whose campaign to create an Islamic state in the religiously mixed country has led to the deaths of about 3,000 people in the past four years. After attacks that left several hundred people dead in the previous fortnight in towns near Maiduguri, on May 14th President Goodluck Jonathan declared a state of emergency in the three states where Boko Haram has built its stronghold: Borno (whose capital is Maiduguri), Yobe and Adamawa. Mr Jonathan has admitted that his forces had lost control of parts of the north-east. Thousands of extra troops are now trying to oust Boko Haram fighters from hiding places. Helicopters have destroyed camps and weapons caches. Telephone lines have been cut in an effort to disrupt the group’s communications. Districts thought to be sympathetic to Boko Haram were put under a 24-hour curfew.

After a week of fighting, Mr Jonathan said his troops had made a breakthrough. “Insurgents have been dislodged from their previously safe havens and camps, while many have been apprehended and their activities in the affected states have been brought to a total halt,” claims the presidency in a statement. He has offered an amnesty, urging the rebels to surrender their arms. The defence ministry said it would free some suspects, including all female detainees, one of Boko Haram’s chief demands. This mix of carrot and stick has boosted the president’s approval ratings in the rest of the country.

But that is not yet the picture in Maiduguri, where the group was founded. Its residents fear the campaign will fail to finish off the rebels, leaving the most hardened to pursue vengeance. In the past the militants have simply vanished into the desert, only to resurface later. “Every time the army is seen to defeat them, Boko Haram regroup and come back stronger,” says Stella Onyebuchi, a local journalist who has long been tracking the rebellion. “This quiet we have now may be short-lived.”

The price of staple goods has sharply risen in Maiduguri, since lorries bringing supplies were prevented from entering the state. Beneath a leafy tree, a female trader balancing a plate of eggs on her head argues with a customer who says the price has doubled in a day. “We were unaware of the curfew and unprepared,” says a waitress. Curfews have been reduced from round the clock to dusk to dawn. “But the shops are still shut up,” she says. “People are very afraid.” Salesmen sleep beneath trees. “I want to sell but there is no one to sell to,” says Amina Haruna, who peddles fuel on the desolate roadside. “I understand why the military is doing this. They say they will keep going for as long as it takes, but how long is that? How do we know it will be worth it?”