Major attack: Thousands of soldiers were deployed, part of the front was broken VIDEO

Major attack: Thousands of soldiers were deployed, part of the front was broken VIDEO

As reported, Ukraine has now brought thousands of troops into the battle in southeastern Ukraine.

The increase in the number of soldiers and firepower is focused on the southeastern region of Zaporizhzhia, a Western official said.

Fighting has intensified in recent weeks at multiple points along the 1,500-kilometer front line, as Ukraine deploys advanced Western-supplied weaponry as well as Western-trained troops against well-equipped Russian forces, which invaded 17 months ago.

The counter-offensive is a massive military operation, which has probably been prepared for months. Military planners had to organize supplies of ammunition, food, medical supplies and spare parts for the front line. Ukrainian officials have been largely silent on developments on the battlefield since they began early counteroffensive operations, although Deputy Defense Minister Hanna Maliar said troops were advancing toward the city of Melitopol in the Zaporizhzhia region.

While the move could be a tactical ruse and both governments have used disinformation to gain an advantage on the battlefield, such a maneuver would be in line with what some analysts have predicted. Military experts predicted a counteroffensive that would try to break through a land corridor between Russia and the Russian-annexed Crimean peninsula, moving toward Melitopol, which is near the coast of the Sea of Azov.

It could split Russian forces in two and cut supply lines to units further west. The Institute for the Study of War, a Washington-based think tank, said on Wednesday that Ukrainian forces launched a "significant mechanized counteroffensive operation in the western region of Zaporizhzhia", adding that they "appear to have breached certain pre-prepared Russian defensive positions".

Zaporizhzhia is also mentioned by the Russian side, including the Russian Ministry of Defense and several prominent Russian military bloggers. The Moscow-appointed head of the partially occupied Zaporizhzhia region, Yevgeny Balitsky, said that Ukrainian forces tried unsuccessfully to break through Russian defenses in the area on Thursday morning. Kyiv forces "suffered significant losses and retreated to (their) positions," Balistky said.