The brave firefighters who battled the raging fire earlier this week at Notre Dame Cathedral in Paris had robotic helpers by their sides and in the sky. A mobile robot named Colossus and two DJI drones helped extinguish the fire and save the 850-year-old historic structure from completely collapsing.

Colossus, made by French company Shark Robotics, is about 2.5 feet wide and 5.25 feet long and can be remotely controlled from almost 1,000 feet away. To help battle the Notre Dame fire, Colossus reportedly fired 660 gallons of water per minute using a motorized water cannon.

The 1,100-pound Colossus robot is resistant to thermal radiation and is completely waterproof. Shark Robotics says Colossus’ lithium-ion batteries can last up to eight hours, and that the robot can be equipped with cameras, sensors and a smoke-extracting fan.

Dramatic footage in the video below shows Colossus spraying water inside the smoke-filled cathedral.

Colussus helped lower temperatures inside the cathedral and save human lives, said Jean-Claude Gallet, commander of the Paris Fire Brigade.

“Time was against us, the wind was against us, and we had to get the upper hand,” Gabriel Plus, a spokesman for the fire brigade, told the Times of London. “The priority we set was to save the two belfries. Imagine if the timber of the belfries had been weakened, and the bells had collapsed. That was really our fear. In the beginning, it was not impossible to imagine that the cathedral structure could collapse.”

Cyril Kabbara, co-founder of Shark Robotics, told the New York Post that Colossus “is a robot that is designed to remove humans from danger. Not to replace [humans] but to act as operational support for firefighters.”

Colossus isn’t the only firefighting robot out there. Mitsubishi Heavy Industries has developed two firefighting robots: the “Water Cannon Robot” and the “Hose Extension Robot.” These robots are designed for situations too hazardous for firefighting crews, such as fires at chemical plants.

A 2016 video shows firefighting robots in China taking part in drills alongside human firefighters at Beijing’s Palace Museum. Lockheed Martin developed a robotic firetruck called Fire Ox, and Howe and Howe Technologies has developed several firefighting robots designed to operate in industrial environments using foam or water.

The U.S. Navy has also experimented with a 5-ft., 10-in. humanoid robot to fight fires, but a humanoid form factor now appears to be a less useful than that of Colossus.

Aerial drones provide eyes in the sky

The Paris Fire Brigade also had robot friends watching from above. According to French newspaper Libération, firefighters used two commercial drones from DJI, the Mavic Pro and Matrice M210. They were equipped with thermal cameras and tracked how the fire was spreading to help figure out where the flames started. The aerial vantage point also helped firefighters determine the best plan to tackle the blaze.

DJI has been in some trouble recently, as one of its drones was spotted illegally flying over Fenway Park during a Boston Red Sox game. DJI said its geofencing technology, which should have prohibited any drones to fly over Fenway during the game, was deliberately over-ridden. There should have been a geofence over central Paris as well, but it appears the restrictions were temporarily lifted to allow the drones to fly over Notre Dame.

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

Brian Lattimer, vice president of research and development at the safety engineering and consulting firm Jensen Hughes, told The Washington Post that firefighting robots will eventually become more autonomous.

“The goal will be for firefighters to be in the loop with these robots to assist and evaluate the hazards so they can plan an effective response,” he said. “Eventually, we’ll have collaborative teams of robots — in the air and on the ground — that will work closely with people and reduce the risk to human life.”