SLAVYANSK, Ukraine - Ukraine on Saturday expanded a military operation to seize ground from rebels in the east, following the bloodiest day in the country since the Western-backed government in Kiev came to power.
Interior minister Arsen Avakov said his forces had launched a dawn raid near the town of Kramatorsk, taking back a TV tower as Kiev struggles to wrest back control of the east amid a pro-Russian insurgency that threatens to tear the country apart.
Saturday's fresh assault came after the deadliest day in months in crisis-hit Ukraine, with dozens killed in clashes and a fire in the southern port city of Odessa and at least nine killed during a military raid on the flashpoint town of Slavyansk.
As the violence on the ground boiled over, the war of words between Moscow and Washington also intensified. The stakes are rising in the worst East-West crisis since the end of the Cold War.
Russia said Ukraine was heading for "catastrophe" and urged it to stop "waging war against its own people". Moscow's envoy to the UN Security Council told a hastily called meeting that Kiev was responsible for the chaos and accused the West of backing it.
Moscow has also declared a peace accord signed last month in Geneva, which was meant to defuse the crisis, a dead letter.
US President Barack Obama meanwhile increased the pressure on President Vladimir Putin, threatening to whack Moscow with its toughest sanctions yet if Russia continued to destabilise its former Soviet republic neighbour.
'We will not stop'
Avakov said the "active phase" of the operation to clear rebels from the east continued at dawn in Kramatorsk, just 17 kilometres (10 miles) to the south of Slavyansk.
"Overnight, forces participating in the anti-terrorist operation in Kramatorsk took control of the TV tower that was previously held by the terrorists," said the minister.
"We will not stop."
He said two rebel checkpoints near the airport had been destroyed.
On Friday, after several days of encircling Slavyansk, the Ukrainian military launched what rebels in the town called a "full-scale" assault with helicopters and armoured vehicles overrunning nine rebel checkpoints.
Two Ukrainian army personnel were killed in the action as rebels shot down two helicopter gunships. Two more died in later fighting, authorities said.
Insurgents said that three of their number and two citizens had died in the operation on Friday.