Russian troops were pinned down by relentless gunfire, believing they were facing multiple Ukrainian fighters. Even under the cover of fog and bad weather, they could not break through.

In reality, the resistance came from a single unmanned ground vehicle deployed by Ukraine's Third Army Corps.

The robot, known as the DevDroid TW 12.7, is no bigger than a ride-on lawnmower but is armed with a .50-calibre M2 Browning machine gun.

It can be operated remotely from up to 15 miles away or navigate terrain using artificial intelligence.

Its commander said the machine defended positions that would normally require up to six soldiers, allowing Ukrainian troops to stay out of harm's way.

Despite daily pressure from Russian forces who attempted to exploit fog, rain, and snow to advance in small groups, every assault was repelled.

'The enemy conducted daily offensive pressure on forward positions,' said Mykola 'Makar' Zinkevych, the NC-13 Strike Company's commander.

The NC-13 Strike Company is a unit within the Third Army Corps that specialises in uncrewed ground vehicles, or UGVs. 

'Until the very end, the enemy was unable to determine that an unmanned ground vehicle (UGV) with a combat module was present at the position.'

The drone briefly left its post every two days for maintenance and ammunition resupply by a crew stationed around 2.4 miles from the front line.

Each session took around four hours and included servicing the weapons, restocking ammunition, and recharging the drone's battery. 

The DevDroid TW 12.7 has an operational range of up to 15 miles and is primarily controlled remotely via radio signal, allowing Ukrainian soldiers to control it from a safe distance.

In addition to manual control, the drone is equipped with artificial intelligence that enables it to plan its own course across the battlefield.

Videos of the drone in action show it moving across rugged terrain and firing multiple quick-fire shots towards Russian positions.