A pro-Russian separatist leader says Ukrainian troops near a Donetsk region town are surrounded and should surrender their weapons or face death.
Russian state news agency RIA Novosti has quoted Aleksandr Zakharchenko as saying rebel forces have surrounded Ukrainian units near Debaltseve, a flashpoint in the recent escalation of a conflict that has killed more than 5,100 people in eastern Ukraine since April.
Zakharchenko reportedly said on January 30 that the Ukrainian troops' lives would be spared if they handed over their weapons.
The demand comes amid expectations of a new round of talks between representatives of the rebels, Ukraine, Russia, and the OSCE on January 30 in the Belarusian capital, Minsk.
The rebels have made gains recenetly in what the United States has called a "Russian-backed offensive" that violates the terms of an agreement on a cease-fire and steps toward peace signed in Minsk in September.
Zakharchenko said on January 23 that the rebels would push to the borders of the Donetsk province and cast deep doubt on their commitment to any cease-fire.
Rocket attacks that killed at least 30 people in the strategic Azov Sea coastal city of Mariupol on January 24 have prompted Western goverments to step up criticism of the rebels and Russia, which Kyiv and NATO says has supported the rebels with troops and weapons during the conflict.
The European Union decided on Januyary 29 to extend until September an initial group of sanctions against Russian and pro-Russia separatist officials due to the continued fighting in eastern Ukraine and has plans for further action.
EU foreign affairs chief Federica Mogherini said on January 29 after an EU foreign ministers' meeting in Brussels that sanctions due to expire in March had been extended by six months.
She added that "we have shown that the EU is ready to take further measures."
The Ukrainian military said heavy fighting and artillery barrages persisted overnight into January 30.
"Ukraine lost five service personnel and another 23 were wounded during firing and military clashes in the past 24 hours," military spokesman Vladyslav Seleznyov said at a brifeing.
A military statement said the rebels used mortars, Grad rocket systems, and artillery in attacks on government positions at Debaltseve -- a key rail and road junction between the rebel-held provincvial capitals of Donetsk and Luhansk -- and in the vicinity of the stratergic Azov Sea coastal city of Mariupol.
It said Kiev's forces were holding their positions and returning artillery and mortar fire when fired upon.
There was no immediate comment from Kyiv on Zakharchenko's claim that Debaltseve was surrounded.
But the Ukranian military said on January 29 that its forces had retreated from the nearby town of Vuhlehirsk, in the face of an onslaught from rebel forces with armored vehicles and tanks, complicating efforts to hold Debaltseve.
Separatists have expressed readiness to attend the talks with the so-called Contact Group -- Ukraine, Russia, and the OSCE -- in Minsk on January 30.
But the leader of the separatists in the Luhansk region, Igor Plotnitsky, told a rebel news agency that the success of the negotiations would hinge largely on lifting what he described as Ukraine's economic blockade of the provonces wher rebels hold territory.
Ukraine is likelky to demand the rebels stop halt their offensive.
Ukrainian President Petro Poroshenko said on January 29 that the talks should lead to "an immediate cease-fire and the withdrawal of heavy weapons from the line of contact" in eastern Ukraine.
With reporting by RIA Novosti, Ekho Moskvy, Reuters, and AP