Ukrainian forces regained more ground but sustained further casualties on Thursday in clashes with separatists, while two Western allies urged Russia's Vladimir Putin to exert more pressure on the rebels to find a negotiated end to the conflict.
Government forces have recently gained the upper hand in the three-month conflict against separatists in the Russian-speaking eastern regions in which more than 200 government troops have been killed as well as hundreds of civilians and rebel fighters.
The Ukrainian military says it has a plan to deliver a “nasty surprise” to the heavily-armed separatists who have dug in in Donetsk, a city of 900,000 people, after being pushed out of their bastion in Slovyansk over the weekend.
In a further success, military spokesman Vladyslav Seleznyov said government forces on Thursday re-took the town of Siversk, east of Slovyansk, when separatists fled.
A separatist confirmed the government's version saying it was “more or less correct.” “There was no sense in holding [Siversk] and reinforcing it because there was a big risk of being encircled.”
But casualties mounted on the Ukrainian side with the deaths of three more Ukrainian soldiers in two attacks on Wednesday night in different parts of the east, the military said.
One was killed in an ambush of a military convoy near Luhansk, while two others died when an armored personnel carrier was blown up by a landmine in the village of Chervona Zorya near Donetsk.
Government forces guarding Donetsk's main international airport, scene of bitter fighting in late May, came under mortar fire on Thursday but the rebel attack was repelled, Seleznyov said.
Reports of torture
Amnesty International says it has "graphic and compelling evidence" of beatings and torture in eastern Ukraine, and it says armed pro-Russian separatists are responsible for the bulk of the violence.
In a report late Thursday, the rights group says victims are "often subjected to stomach turning beatings and torture." It also says there is evidence of a smaller number of abuses by pro-Kyiv forces.
The report says the United Nations Human Rights Monitoring Mission for Ukraine has recorded 222 abductions since April, when separatists seeking autonomy in the east launched their rebellion against the Kyiv government.
Amnesty says abductions have taken place across eastern Ukraine targeting police and local officials. It also cites violence against journalists, politicians, activists, business people and members of electoral commissions.
The report also cites recent Ukrainian military gains in the east, and says captives held by separatists are now being freed by Ukrainian forces almost daily. It says the number of "disturbing" cases is increasing as pro-Kyiv forces gain more ground and free more captives. It also says those cases are being "meticulously" documented and that perpetrators will be brought to justice.
Putting onus on Putin
In further international diplomacy to end the worst Russia-West crisis since the Cold War, French President Francois Hollande and German Chancellor Angela Merkel urged Putin by telephone to “exert all necessary pressure on the separatists to bring them to negotiate effectively,” an Elysee Palace statement said.
They also asked him to use his influence to take concrete steps to ensure control of the border where, the Kyiv government says, Russian authorities have been turning a blind eye to fighters crossing with weapons and equipment to help the rebels.
Moscow protested to Kyiv on Thursday after it said Ukrainian military fired on a Russian border checkpoint. The Foreign Ministry said it was not the first time the border post at Gukovo had come under fire.
Moscow is under sanctions by the United States and the European Union over the Ukraine crisis but denies it is supporting the rebels in the Russian-speaking east of Ukraine.
Russia on Thursday condemned a European Union plan to extend the list of persons, including Russians, targeted with asset freezes and travel bans as an unfriendly move that would hinder ties with the 28-nation bloc.
The EU has agreed to add 11 new names to the list likely to take effect on Saturday, an EU diplomat said on Wednesday.
The rebellions began in April after Russia annexed Ukraine's Crimea peninsula following the overthrow of a Moscow-backed president by mass street protests in Kyiv.
Ukraine's border guard service reported that six Russian helicopters had flown some distance over the border into Ukraine on Wednesday and then returned home in what it described as “direct provocations in support of the terrorists.”
In its version of the three-way telephone call, the Kremlin said the three leaders had agreed on the need for a “swift renewal” of the ceasefire and another round of peace talks involving the “contact group” and separatist leaders.
Ukrainian President Petro Poroshenko refused to prolong a 10-day unilateral ceasefire when it expired on June 30 and ordered a resumption of the military offensive against the rebels resulting in Slovyansk being re-taken over the weekend.
His security chiefs say the rebels repeatedly breached the government's unilateral ceasefire, resulting in many Ukrainian military deaths, and have ruled out any more such truces until the rebels lay down their arms.
Rebels in Donetsk, commanded by a Russian military adventurer called Igor Girkin or Strelkov, say they are recruiting new fighters to resist government forces.
Buoyed by the success in Slovyansk, Ukrainian security officials say they have a plan ready to crush the rebels in Donetsk though Poroshenko has ruled out air strikes and artillery bombardment because of the large civilian population.
The separatists are occupying administrative buildings in both Donetsk and Luhansk and are dug in on the outskirts of Donetsk.
Thousands of people have fled Donetsk, a major industrial hub and Euro-2012 football site, since the onset of the conflict and many businesses are closing down.
With armed men out on the streets, tension is growing in the city. Several social groups came together on Thursday to call on townspeople to join in a daily prayer session at noon every day from next Monday.