Ukraine claims to have successfully staged a dawn raid against pro-Russian separatists in an expansion of operations in the east of the country. In Odessa, scores were arrested after street battles led to a deadly fire.
Ukrainian Interior Minister Arsen Avakov said Ukrainian forces had taken control of a television tower close to the town of Kramatorsk.
"The active phase of the operation is continuing. We will not stop," said Avakov said on his Facebook page.
"Overnight, forces participating in the anti-terrorist operation in Kramatorsk took control of the TV tower that was previously held by the terrorists," added the minister.
Kramatorsk lies about 17 kilometres (10 miles) south of the city of Slovyansk, where the Ukrainian army mounted a major offensive against separatists on Friday. The attack claimed at least nine lives, including two Ukrainian servicemen who died when rebels shot down two army helicopters using surface-to-air missiles.
Talk of elections 'absurd'
Russian President Vladimir Putin's spokesman said on Saturday that, as a result of Ukraine's military operations, the Kremlin no longer had any influence over the rebels.
"From now on Russia essentially has lost its influence over these people because it will be impossible to convince them to lay down arms when there's a direct threat to their lives," Dmitry Peskov said, adding: "to speak about elections is absurd."
Ukrainian police said that, after some 30 people died in a fire and street fighting, they had arrested more than 130 people in the southern port of Odessa.
Police chief Petro Lutsiuk said the detainees could face charges for participating in riots or even premeditated murder. The violence led to the city's trade union building being set on fire.
Ukraine's Friday assault on Slovyansk prompted Russia to call a meeting of the United Nations Security Council.
Russian UN Ambassador Vitaliy Churkin accused the West of interfering in the internal affairs of Ukraine, and said the involvement of "English-speaking foreigners" had been noted in the Slovyansk operation.
"Of particular concern is information that during the punitive operations of the Ukrainian armed forces and illegal ultranationalist groups there was English on the radio waves as well as amongst those attacking in Slovyansk," said Churkin.
US Ambassador Samantha Power accused Moscow of "monumental falsehoods," claiming that the problem in Ukraine was nothing more than "Russian sponsored paramilitary violence."
Russia is believed to have some 40,000 troops on the Ukrainian border, while Kyiv has reintroduced conscription and put its armed force on full combat alert.
rc/jr (AFP, AP, Reuters)
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