The four women lay dazed on the beds of the clinic. The face of one of them was burnt. Another broke her leg during the Nigerian army offensive against Boko Haram Islamists in their village.

Civilians have often been collateral damage in the conflict that has raged in remote northeast Nigeria for nearly eight years, leaving at least 20,000 dead and more than 2.6 million homeless.

The women wait for their wounds to heal in the suffocating heat.

"Boko Haram fighters would come to their village to steal food and hide," a nurse explained. "The army went there and put the women in a truck to evacuate them.

"The military set the village on fire, so the insurgents couldn't hide anymore. But the fire 'jumped' in the truck."

The women, with their heads covered and gold nose rings in the tradition of the ethnic Kanuri group, still look terrified.

They stare at the walls and ignore visitors, afraid that questions will focus too much on the circumstances of the "liberation" of their village.

- Fighters easily blend in -

The nurse says there are no more men left. They were either killed in the fighting, drafted into the civilian militia or forced to join the ranks of Boko Haram.

Some may even be at so-called "screening" centres, where soldiers pass judgement on whether local men have been involved in the insurgency.

Such checks, free from any oversight, can take weeks or months, especially if the men are Kanuri like the majority of Boko Haram.

James Adewunmi Falode, a security analyst at the University of Lagos who tracks the conflict, said Boko Haram's resemblance to "ordinary citizens" was making the fight against them harder.

"They are not a military adversary that can be easily identified and destroyed on the battlefield. These people can easily blend into the general population when the situation demands," he said.

Even women and children, who have been repeatedly used by the group as as human bombs, are a potential threat, explaining the tensions between the military and the public.

- 'Just criminals' -

Around Dikwa and a dozen or so other secured major towns, villages have been emptied to prevent them being used by the jihadists as hideouts or resupply points.

The military also wants to stop the mass kidnapping of their inhabitants.

"Before, they (Boko Haram) would read the Koran and try to change us," said Bulama Goni, a former village chief with a white beard in long, flowing robes.

"Now, they are just criminals, asking for money, looking rough and disgusting."

Boko Haram fighters are also starving: Nigerian army tactics have been to slowly choke the rebels, cutting off their supplies of arms and food. The strategy appears to be working.

Boko Haram used to attack major towns and cities in northeast Nigeria and in 2014 controlled territory as big as Belgium.

But now it is limited to sporadic suicide bomb attacks and ambushes of military convoys and check-points.

The military's isolation strategy, however, has not seen everywhere secured and has had an effect on the daily life of civilians.

More than five million people are in desperate need of food, according to the United Nations.

"In liberated areas there is no fuel, no communication, no public transport... even the food it's all controlled by the army," said one security operative for a major international aid agency.

"This is a classical counter-insurgency strategy left over from the Vietnam war. It hasn't changed but it's not sustainable," he added.

- Suspicious activity -

Monguno, in the north of Borno state, is a former trading hub near the edge of Lake Chad, the watery border between Nigeria, Niger, Chad and Cameroon.

There are currently about 100,000 people in the town's camps. But some 27,000 people are waiting for food distribution.

According to Ibrahim Maina, the coordinator for the Borno state emergency management agency, the last handouts were in November last year. Everyone's face is etched with hunger.

The road linking Monguno to the state capital Maiduguri, 137 kilometres (86 miles) away, has been reopened.

Muhammadu Sanni, goes to the shores of Lake Chad once a week to catch catfish to feed his family. But he says he can't catch a lot.

"If (the military) stop me with a lot of fish, they will think I'm smuggling for Boko Haram," he said, as he fixed his nylon net.

"I will go back to screening and it will take a long time."