Ukrainian President Petro Poroshenko has vowed to continue Kyiv's military offensive against pro-Russian separatists. Government troops have advanced to Donetsk after capturing the rebel stronghold of Slovyansk.
Calling the capture of Slovyansk a major "turning point," President Poroshenko ordered Ukrainian forces on Sunday to push on with their offensive against pro-Russian separatists in the eastern regions of Donetsk and Luhansk.
"My order is now in effect - tighten the ring around the terrorists," Poroshenko tweeted on Sunday. "Continue the operation to liberate Donetsk and Luhansk regions," the president said.
On Saturday, Ukrainian troops forced the rebels out of Slovyansk, in Kyiv's first major military victory since fighting broke out in April. Kyiv has launched an all out offensive with tanks, artillery and helicopter gunships.
"This is not a full victory," Poroshenko said. "But the clearing out of people armed to the teeth from Slovyansk has huge symbolic importance. It is the beginning of the turning point in the battle with fighters for the territorial integrity of Ukraine."
Ukrainian forces claim to now have full control of both Slovyansk and the nearby city of Kramatorsk, both located in the Donetsk region. The two cities have populations of fewer than 200,000 people.
'Real partisan war'
The self-declared commander in chief of the separatist Donetsk People's Republic, Igor Girkin, claimed that 80 to 90 percent of the rebels escaped from Slovyansk unharmed. But he admits that a number of militants perished in a botched attempt at a diversionary attack.
Many rebels have retreated to the city of Donetsk, the capital of the Donetsk region. Donetsk city has a population of around one million people. Rebel leader Girkin has vowed to continue the fight against Ukraine's pro-Western government.
"We will continue the combat operations and will try not to make the same mistakes that we made in the past," said Girkin, also known by his Russian nom de guerre, Igor Strelkov.
At a rally in a square in Donetsk on Sunday, people waved the flags of Russia and the Donetsk People's Republic. Pavel Gubarev, the self-described governor of the breakaway region, told the crowd that rebel forces would fight to defend the city.
"We will begin a real partisan war around the whole perimeter of Donetsk," Gubarev told the crowd. "We will drown these wretches in blood."
slk/hc (Reuters, dpa)