Fighting is continuing to rage in the eastern Ukrainian city of Donetsk as the military dismissed calls for a ceasefire by pro-Russian rebels.
At least one person was killed and 10 injured as government shelling continued throughout Sunday in the rebel-held city, despite an appeal by a rebel leader for a ceasefire on humanitarian grounds.
According to reporters, more than 10 residential buildings, as well as a hospital and a shop, were heavily damaged by overnight shelling.
At least 25 loud explosions occured in as many minutes around noon on Sunday.
Ukraine's military spokesman told the Reuters news agency a cessation of fighting would only occur if the rebels raised "white flags" and surrendered.
On Saturday, rebel leader Aleksandr Zakharchenko called for a ceasefire to avert a "humanitarian catastrophe," but his request was met warily by both the Ukrainian government in Kiev and the West.
The calls for a ceasefire have been seen as a way of pressuring Ukraine to allow in a Russian aid mission. The West says that could be used as a pretext to bring Russian soldiers into Ukraine.
Ukraine's President Petro Poroshenko and Western leaders have repeatedly accused Moscow of providing arms and expertise to the rebels, something Russia denies.
Fighting in Donetsk has forced at least 300,000 of the city's one million residents to flee.
"This is a real war! It's impossible to live in this city, I've been sleeping in the basement for the past week," Inna Drobyshevskaya, a 48-year-old lawyer said.
"We don't want Novorossiya for this price," she said, referring to a term used by rebels to describe the parts of eastern Ukraine seeking independence from the government in Kiev.
Russia releases Ukrainians
Russia has released another five Ukrainian soldiers who crossed into the country last week and handed them over to Ukraine.
Moscow claimed they had surrendered and were switching sides, but Kiev said they were forced to withdraw over the border after running out of ammunition in battles with the separatists.
"At 1.40 am, Russia handed over to Ukrainian border guards five troops ... who had been illegally detained on the territory of the Russian Federation," the council's spokesman Andriy Lysenko said.
Russian investigators had originally accused the soldiers of using heavy weapons indiscriminately, wounding or killing at least 10 civilians and destroying 20 homes in the region near the eastern Ukrainian rebel-held city of Lugansk.
However, Vladimir Markin, the spokesman for the Russian Investigation Committee, told state news agency Ria Novosti that "the probe revealed that the men only followed orders from their command and did not directly commit any crimes".
War crimes charges would have carried penalties of up to 20 years in prison.