KYIV, UKRAINE -- A nighttime Russian attack destroyed trains and tracks in Ukraine’s northeastern Kharkiv region, officials said Friday, and authorities organized the evacuation of children from the area as it is being pummelled by the Kremlin’s forces in a powerful new offensive.

The overnight strike on rolling stock and railway tracks also damaged buildings, according to Ukraine’s national railway operator Ukrzaliznytsia. No injuries were reported.

Authorities have evacuated more than 11,000 people from the Kharkiv region since Russia launched an offensive there on May 10, regional Gov. Oleh Syniehubov said. Officials on Friday announced the mandatory evacuation over the next 60 days of 123 orphans and children living without their parents in the area.

Russia’s Kharkiv push appears to be a co-ordinated new offensive that includes testing Ukrainian defences in the Donetsk region further south, while also launching incursions in the northern Sumy and Chernihiv regions. Russian President Vladimir Putin has said the Kremlin’s army is attempting to create a “buffer zone” in the Kharkiv region to prevent Ukrainian cross-border attacks.

Ukraine’s problems have been mounting in recent months as it tries to hold out against its much bigger foe, and the war appears to be at a critical juncture.

Ukraine's ranks depleted

The new Russian offensive is stretching thin Ukraine’s depleted ranks, exhausted by more than two years of war. Destroying the train network puts further pressure on the already overstretched Ukrainian army.

Crucial western aid for Kyiv, especially air defence systems to stop Russia’s targeted destruction of the power grid, isn’t arriving quickly enough. Also, most western donors won’t let Ukraine use the sophisticated long-range weapons they are providing to strike targets on Russian soil. That allows Moscow to assemble virtually unimpeded its troops for cross-border assaults, as well as deploy missile launchers to bombard Ukraine.

Ukrainian President Volodymyr Zelenskyy said those limitations made possible an attack on the city of Kharkiv, the region’s capital, on Thursday that killed seven civilians and wounded 21 others.

Zelenskyy said on social media that Ukraine has “a shortage of air defense systems that are actually available in the world” and a “lack of long-range capabilities for our warriors and the complete inability to destroy the very source of Russian terror near our borders, including the missile launchers that actually hit Ukraine and the lives of our people.”

The Ukrainian military said Friday it had stopped the Russian advance in the north of the Kharkiv region and were conducting counter-offensive operations.

A Russian troop build-up in the Sumy and Chernihiv regions, however, is ongoing, with daily air and artillery strikes, according to Ihor Prokhorenko, a general staff spokesman.

It was not possible to independently verify the claims.

Thursday’s strike on Kharkiv using S-300 missiles hit a printing company, burning about 50,000 books, Zelenskyy said.

Serhii Polituchyi, owner of the Faktor-Druk printing plant, said the attack would reduce Ukraine’s book-printing capacity by 30 to 40 per cent.