While the city of Paris recovers from the devastating fire that engulfed the 850-year-old Notre Dame cathedral on Monday, some unlikely heroes have emerged.

Local firefighters are praising the DJI drones that were used to track the progression of the blaze and find the best position to aim the fire hoses.

“The drones allowed us to use our available means in the best possible way,” a local firefighter told FranceInfo.

“It is thanks to these drones, to this new technique absolutely essential today, that we were able to make tactical choices to stop this fire at a time when it was potentially occupying the two belfries.”

The Parisian Police Drone Unit cell was called on to control the drones used during the incident.

The damage of the fire – which is expected to cost almost $8 billion in repairs – could have been significantly worse if the drones had not been used.

Reports have suggested that the two front towers of the structure did not incur any structural damage.

Paris is usually a drone-free zone and operators require credentials to unlock the ‘geofencing’ controls that prevent flying.

It is believed the firefighters used a DJI Mavic 2 Enterprise Dual drone and an M210 borrowed from the Culture and Interior ministries.

A DJI spokesperson said that firefighters “have now integrated and digested out technology so they can fully adopt it in search and rescue missions...[and] in extinguishing fires like what we saw in Notre Dame.”

DJI also recently inked a deal with the Los Angeles Fire Department (LAFD) to help better use drones as an emergency response tool.

The agreement will see drones equipped with thermal imaging cameras deployed to deliver real-time video and data transmission to incident commanders.

The NSW Fire & Rescue is also now using drone technology to gather real-time images of areas too dangerous to access.