Ukrainian soldiers fighting in Russia’s Kursk region have described scenes “like a horror movie” as they retreated from the front lines.

The BBC has received extensive accounts from Ukrainian troops, who recount a “catastrophic” withdrawal in the face of heavy fire, and columns of military equipment destroyed and constant attacks from swarms of Russian drones.

The soldiers, who spoke over social media, were given aliases to protect their identity. Some gave accounts of a “collapse” as Ukraine lost Sudzha, the largest town it held.

Ukrainian restrictions on travel to the front have meant it is not possible to get a full picture of the situation. But this is how five Ukrainian soldiers described to us what had happened.

On 9 March, “Volodymyr” sent a telegram post to the BBC saying he was still in Sudzha, where there was “panic and collapse of the front”.

Ukrainian troops “are trying to leave – columns of troops and equipment. Some of them are burned by Russian drones on the road. It is impossible to leave during the day.”

Movement of men, logistics and equipment had been reliant on one major route between Sudzha and Ukraine’s Sumy region.

Volodymyr said it was possible to travel on that road relatively safely a month ago. By 9 March it was “all under the fire control of the enemy – drones around the clock. In one minute you can see two to three drones. That’s a lot,” he said.

“We have all the logistics here on one Sudzha-Sumy highway. And everyone knew that the [Russians] would try to cut it. But this again came as a surprise to our command.”

At the time of writing, just before Russia retook Sudzha, Volodymyr said Ukrainian forces were being pressed from three sides.

By 11 March, Ukrainian forces were battling to prevent the road being cut, according to telegram messages from “Maksym”.

“A few days ago, we received an order to leave the defence lines in an organised retreat,” he said, adding that Russia had amassed a significant force to retake the town, “including large numbers of North Korean soldiers”.

Military experts estimate Russia had amassed a force of up to 70,000 troops to retake Kursk – including around 12,000 North Koreans.

Russia had also sent its best drone units to the front and had was using kamikaze and first-person-view (FPV) variants to “take fire control of the main logistics routes”.

They included drones linked to operators by fibre-optic wires – which are impossible to jam with electronic countermeasures.

Maksym said as a result “the enemy managed to destroy dozens of units of equipment”, and that wrecks had “created congestion on supply routes”.

The situation on that day, 11 March, was described as “catastrophic” by “Anton”.

The third soldier spoken to by the BBC was serving in the headquarters for the Kursk front.

He too highlighted the damage caused by Russian FPV drones. “We used to have an advantage in drones, now we do not,” he said. He added that Russia had an advantage with more accurate air strikes and a greater number of troops.

Anton said supply routes had been cut. “Logistics no longer work – organised deliveries of weapons, ammunition, food and water are no longer possible.”

Anton said he managed to leave Sudzha by foot, at night – “We almost died several times. Drones are in the sky all the time.”

The soldier predicted Ukraine’s entire foothold in Kursk would be lost but that “from a military point of view, the Kursk direction has exhausted itself. There is no point in keeping it any more”.

Western officials estimate that Ukraine’s Kursk offensive involved around 12,000 troops. They were some of their best trained soldiers, equipped with western-supplied weapons including tanks and armoured vehicles.

Russian bloggers published videos showing some of that equipment being destroyed or captured. On 13 March, Russia said the situation in Kursk was “fully under our control” and that Ukraine had “abandoned” much of its materiel.

In social media posts on 11-12 March, a fourth solider, “Dmytro” likened the retreat from the front to “a scene from a horror movie”.

“The roads are littered with hundreds of destroyed cars, armoured vehicles and ATVs (All Terrain Vehicles). There are a lot of wounded and dead.”

Vehicles were often hunted by multiple drones, he said.

He described his own narrow escape when the car he was travelling in got bogged down. He and his fellow soldiers were trying to push the vehicle free when they were targeted by another FPV drone.

It missed the vehicle, but injured one of his comrades. He said they had to hide in a forest for two hours before they were rescued.

Dmytro said many Ukrainians retreated on foot with “guys walking 15km to 20km”. The situation, he said, had turned from “difficult and critical to catastrophic”.

In a message on 14 March, Dmytro added: “Everything is finished in the Kursk region… the operation was not successful.”

He estimated that thousands of Ukrainian soldiers had died since the first crossing into Russia in August.

A fifth soldier sounded less gloomy about the situation. On 13 March, “Artem” sent a telegram message from a military hospital, where he was being treated for shrapnel wounds suffered in a drone attack.

Artem said he had been fighting further west – near the village of Loknya where Ukrainian forces were putting up a stiff resistance and “fighting like lions”.

He believed the operation had achieved some success.

“It’s important that so far the Armed Forces of Ukraine have created this buffer zone, thanks to which the Russians cannot enter Sumy,” he said.

Ukraine’s top general, Oleksandr Syrskyi, insists that Ukrainian forces have pulled back to “more favourable positions”, remain in Kursk and would do so “for as long as it is expedient and necessary”.

He said Russia had suffered more than 50,000 losses during the operation – including those killed, injured or captured.

However, the situation now is very different to last August. Military analysts estimate two-thirds of the 1,000 sq/km gained at the outset have since been lost.

Any hopes that Ukraine would be able to trade Kursk territory for some of its own have significantly diminished.

Last week, President Volodymyr Zelensky said he believed the Kursk operation had “accomplished its task” by forcing Russia to pull troops from the east and relieve pressure on Pokrovsk.

But it is not yet clear at what cost.