The battle is playing out not only on Mosul's streets but also in cyberspace, where both jihadist and Iraqi forces use online media and social networks to mobilise or demoralise.

Many in the government camp feel that, in June 2014, Mosul was lost to the Islamic State group before a shot was even fired in anger, and they are keen not to lose the media war a second time.

"The media and social networks announced the fall of Mosul before it even happened, and as result, well, it fell," said one fighter who had witnessed the debacle that saw IS seize Iraq's second city.

Now that his unit is working its way back into Mosul as part of the massive offensive launched against IS there on October 17, he argued "the same tools should be used to the advantage" of the Iraqi forces.

Since the start of the assault, Iraq's largest military operation in years and the one meant to deal a death blow to the "caliphate", the central command has released a steady stream of victorious statements.

National media outlets have been beaming hours of raw footage from the front lines, including the Kurdish channel Rudaw that live-streamed the first days of the war embedded with peshmerga fighters.

Hundreds of thousands of internet users connected to the feed daily until the authorities eventually saw the down side of showing real-time troop movements on television.

"For the Kurds, it is political. They are boosting the morale of the base and sending a positive image to the West," said Francois-Bernard Huygue, a researcher at the Paris-based IRIS institute.

Now the local Mosul channel is gradually returning to its city, in the wake of the elite Counter-Terrorism Service and army forces retaking ground from IS.

But in addition to the television networks, other channels of communication are just as effective in broadcasting the war.

- 'Pure terror' -

Besides a weapon and ammo, every fighter's kit includes a smartphone and charger, usually plugged into his military vehicle's battery.

Most fighters have hundreds of pictures in their phones, mostly selfies and photos of jihadist corpses, some of which they post on social media when the connection is good enough.

Propaganda was also one of IS's strong points, Huygue argued.

"If Al-Qaeda was more web 1.0, then Daesh, which is very present on social media, is clearly web 2.0," said the cyberstrategy expert, using an Arabic acronym for IS.

"It relies on the participation of jihadists who use GoPros and BlockBusters and creates an impression of pure terror," he said, referring to small cameras mounted on anything from helmets to remote-controlled offroad vehicles.

He argued that the general public is growing accustomed to images of war and atrocities and, faced with a profusion of narratives online, everybody "can choose their version of the story and decide who are the goodies and who are the baddies".

Civilians living in IS-controlled areas have had limited access to social media because simply owning a SIM card was punishable.

Over more than two years of jihadist rule, however, the social media accounts of one Mosul resident have provided regular updates about daily life in the de facto Iraqi capital of IS's self-proclaimed "caliphate".

The individual who goes by the alias "Mosul Eye" is a self-described "independent historian", and the content is in both Arabic and English.

With Iraqi forces slowly retaking neighbourhoods in the city where hundreds of thousands of people still live, the clandestine blogger continues to provide up-to-the-hour reports on the situation inside Mosul.

Some of the latest tweets are about the price of a kilo of rice or a bottle of gas in the battered city, where basic supplies are running low.

The blogger behind Mosul Eye recently announced that he or she had to leave the city, however: "I was compelled to leave my beloved city, and I have no idea if I will ever go back one day."