Russia’s summer offensive in eastern Ukraine, launched in May, is showing battlefield gains across multiple fronts, probing and attacking with small, fast-moving units as fighting escalates daily.

With its advance, Russia has shifted the war’s rhythm. In May, Russian forces seized roughly 173 square miles, more than double April’s gains, according to DeepState, a Ukrainian group that maps the conflict using combat footage. Most gains came south of Kostyantynivka, in the Donetsk region, and near the Russian border in the northern Sumy region.

In a new development this spring, both sides have turned to motorcycles and civilian cars to quickly cross open terrain. Ukraine, which relies heavily on drones to hold its positions, is using civilian vehicles to resupply its defensive lines, while Russia uses them in assaults.

“It’s a kind of renaissance of the cavalry, but with internal combustion engines,” said Col. Viktor Kevliuk, a Ukrainian Army reservist and an analyst at Ukraine’s Center for Defense Strategies, a think tank.

Here are the areas where the front is moving.

Sumy

In recent months, Russian troops have captured at least a dozen villages in the Sumy region. The advance is tiny, but in frequent steps, with small assault groups, often just two or three Russian soldiers, who probe Ukrainian positions in waves.

“Where the last surviving infantry is holding out, the next assault group arrives to build on any success,” Colonel Kevliuk said.