Russia is massively applying a new tactical method to break through the Ukrainian defenses in populated areas — the so-called. infiltration: covert entry of small assault groups into the rear of advanced Ukrainian units, entrenchment in the urban built-up area and subsequent actions to disrupt the command, supply and support systems of Ukrainian forces.
Analysis of the fighting in recent months shows that this method is used in Pokrovsk, Kupyansk and other directions and brings both surprises and risks for both attackers and defenders, writes a BBC analysis.
In August, Russian units suddenly made a deep double breakthrough north of Pokrovsk towards Dobropolie, wedged into Ukrainian positions by more than 10 kilometers each. In October, it became clear that there had been a penetration of infantry units into large areas of Pokrovsk itself - a number of Ukrainian positions were effectively cut off and threatened from the rear. Similar actions were also seen in Kupyansk, where assault groups penetrated the central regions unnoticed and intensified the fighting there.
The classic mass assaults - with siege attempts and open, bloody attacks - led to heavy losses for both sides at Bakhmut and Avdeevka.
At the same time, the spread of tactical combat and reconnaissance drones created "kill zones" along the front, where any attempt to move is detected and destroyed. This changed the field: armored vehicles and supporting firepower must remain further back, and infantry often suffers heavy losses when going out to attack. Under pressure from the top leadership, the Russian command began to actively seek alternatives — and reached infiltration.
How does infiltration work?
The tactic is complex and, according to Ukrainian military expert Konstantin Mashovets, can be broken down into three main stages:
Preparatory stage — reconnaissance (radio, space, drone) to detect vulnerable areas and identify drone operators, supply routes and rotation points. Intensive artillery and air activity, electronic warfare (EW), sabotage to create a breakthrough in Ukrainian defense.
Practical stage — covert, synchronous introduction of multiple small assault groups (often moved by light vehicles: motorcycles, quads, buggies, and sometimes by light vehicles such as scooters), camouflage as civilians and use of night movements. The goal is to disrupt defenses by attacking command posts, drone operators, and logistics chains. The infiltrated groups equip hidden positions and receive reinforcements (often delivered by drones).
Consolidation and development stage — when disorganization is sufficient, the main Russian forces attempt to link up with the breached groups and use the opening for further offensive.
In an urban environment, infiltration has specific advantages: multiple cover, the ability to move near civilian buildings, and a high potential for fragmentation of defenses. However, the method requires precise preparation and coordination; success is not guaranteed. There are examples of failures — Russian airborne troops in Chasov Yar failed to penetrate deeply and suffered heavy losses, and on the Dobropol direction the breakthrough was soon closed by Ukrainian reserves and the bridgehead disappeared.
What does this mean for Ukraine?
The infiltration revealed several key vulnerabilities in the Ukrainian defense: personnel shortages in some areas, exposed areas in the tactical lines, problems with rotations and supply, as well as a risk to drone operational groups. An effective response requires a combination of measures: reinforcement and more frequent rotation of front-line units, protection of drone operators (physically and through electronic warfare), retention of control over key logistical nodes, counterintelligence, and more active patrol and counterinfiltration operations.
Limitations of this tactic
Experts emphasize that infiltration is most effective in dense urban environments; in open spaces, its success is questionable. Techniques such as fiber-optic drones, electronic warfare, and adequate artillery support remain key to repelling infiltration attempts. In addition, the method is resource-intensive and is a temporary solution — in the absence of subsequent massive reinforcements, breaches can be eliminated.
The new Russian practice shows an adaptation at the tactical level: from brute force to more complex, coordinated operations in order to avoid the huge losses of open assaults. It provides opportunities for quick gains in cities like Pokrovsk and Kupyansk, but it is not a panacea. The long-term effect depends on the ability of both sides to adapt their intelligence, logistical and other countermeasures, as well as on the availability of reserves to decide whether temporary success will turn into a strategic shift.