Ukrainian authorities say at least 15 people are dead after rockets hit a market in the key port city of Mariupol.
The attack in a residential area came just hours after the rebel leader in the Donetsk region said there will be no further peace talks with Kyiv. Officials say at least 74 people were wounded.
Mariupol sits on the Azov Sea between mainland Russia and the Russia-annexed Crimean Peninsula.
On Friday, Russian-backed Alexander Zakharchenko, head of the self-declared Donetsk People’s Republic, said his forces would attack government troops until reaching the borders of the Donetsk region. He said his fighters were advancing against Ukraine combat troops after seizing control of a long-contested airport on Thursday.
Separatists currently control key territory in the Donetsk and Luhansk regions near the Russian border, after launching a rebellion nine months ago against Ukraine rule.
Zakharchenko was quoted in Russian media as saying he saw “no point” in further four-party peace talks. He told Interfax news agency the Minsk peace talks format agreed on last year was “a mistake” that “we will not make again.”
Separately, Russia’s Interfax news agency quoted rebel military official Eduard Basurin as saying more than 750 Ukrainian troops have been killed in recent days, in the battle for the now-destroyed Donetsk airport.
He said more than 100 Ukraine tanks and other fighting vehicles have also been destroyed. The rebel claims have not been independently confirmed. U.N. officials, relying on reports from the conflict zone, say they have tallied 262 deaths in the past nine days.
In Moscow Friday, Russian President Vladimir Putin blamed Ukraine for the latest escalation of violence. He accused Kyiv of launching an offensive using artillery and aviation that he said has killed or wounded dozens of people, including women, children and the elderly.
Doctors Without Borders said Friday that the situation for civilians caught in the conflict zone is now “dire.” The international medical charity said doctors close to the frontline are “struggling to treat the wounded with dwindling supplies,” while heavy fighting prevents medical teams from reaching the hardest-hit areas.
The United Nations human rights agency said Friday that the death toll from the conflict has passed 5,000. But spokesman Rupert Colville said the death toll could be far higher.
In Washington Friday, State Department spokeswoman Jen Psaki said the U.S. remains deeply concerned by the increasing violence and bloodshed in eastern Ukraine, which she said has has resulted from a surge in Russia-backed separatist attacks against the cease-fire line in what appears to be a general offensive. She said Russia-backed separatists have carried 1,000 attacks since early December.
Psaki said Russia is actively supporting the separatists by supplying them with heavy weaponry and vehicles, including tanks, armored personnel carriers, and heavy artillery pieces, as well as providing military personnel for exercising ongoing tactical support.
She again called on Russia to stop the flow of heavy weapons, fighters, and advisors, and restore Ukraine’s control along its side of the international border and allow OSCE monitoring along both sides of the border.
