Pro-Russia rebels chased from eastern Ukraine strongholds blew up three bridges leading to the regional capital of Donetsk on Monday in an apparent effort to thwart the further advance of a reinvigorated Ukrainian army.
Government troops took four key towns from the separatist rebels over the weekend, including Slovyansk, a front-line bastion of the fighting that broke out in April weeks after Russia seized and annexed Ukraine's Crimea region.
Russian media continue to cast the Ukrainian government's campaign to recover territory occupied by the militants as "punitive" action against Russian-speaking eastern residents who want regional authorities to have more say over their finances and foreign relations.
Ukrainian officials have proclaimed the military successes of the last few days a watershed moment in the 3-month-old conflict.
"According to our intelligence, the morale of militants is extremely low because they feel abandoned, betrayed and deceived," Interior Ministry advisor Anton Heraschenko told reporters at a briefing in Kiev, the capital. He described the government forces as bolstered by the "turning point" marked by their weekend recovery of Slovyansk, Kramatorsk, Artemivsk and Druzhkivka.
The office of President Petro Poroshenko reported Monday that government troops had also recaptured Kostyantynivka and raised Ukraine's yellow-and-blue national flag over the Donetsk region town after clearing land mines and roadblocks left by the rebels.
But militants who escaped from their former strongholds before troops moved in have converged on the city of Donetsk, the capital of the heavily industrialized Donbass basin that spans eastern Ukraine between the Don and Dnieper rivers.
In an apparent effort to frustrate any government move against Donetsk, a city of 1 million residents before the conflict, the separatist gunmen blew up three key bridges, including a railroad span over the highway between Donetsk and Slovyansk. News agencies in the region said part of an 11-car freight train was left suspended on the collapsed and dangling track.
Ukrainian and Western officials have accused Russian President Vladimir Putin of arming and instigating the separatists, who began seizing government buildings and security facilities in Donetsk and Luhansk regions shortly after Russia seized Crimea. Russian officials deny they are orchestrating the fighting, and Putin has so far ignored appeals from the rebels to their areas annexed to Russia as well.
On Monday, the self-proclaimed governor of the so-called Donetsk People's Republic said the rebels were gearing up to carry out a major counteroffensive. But in a veiled appeal to Putin for aid, Pavel Gubarev said the rebels were unlikely to succeed without backing from Russia, the Kyiv Post quoted him as saying in a report posted on the newspaper website.
As the rebels were regrouping in Donetsk, from which much of the civilian population has fled, Ukraine's wealthiest magnate urged both sides to refrain from damaging infrastructure that will be needed to heal the region's deep economic wounds.
Akhmetov, whose fortune is estimated at $11 billion, owns and operates mines, steel foundries, shipyards and other major industries in the Donbass region and has been warning for months that the conflict is destroying the economy as well as national unity.
A rebel attempt to take control of the international airport in Donetsk in May led to major fighting and closure of the vital transportation hub. Rail traffic into and out of Donetsk has been repeatedly disrupted by the clashes, thwarting reliable delivery of goods from Donbass factories and mines. Government forces have also had to locate and defuse land mines around the towns they have recovered.
While the retreating separatists are leaving paths of destruction behind them, government forces have regained control of most border crossings with Russia and are now able to prevent the influx of weapons and mercenaries, Defense Ministry spokesman Andriy Lysenko told reporters in Kiev.
Nearly 500 people have died in the fighting in eastern Ukraine, including 200-plus Ukrainian troops and dozens of civilians caught in the crossfire.
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