Fighting flares near Ukrainian border city
Fighting has flared outside the rebel-held east Ukrainian city of Luhansk, with rebels saying government forces tried to storm the city with tanks.
Russia threatened Ukraine on Sunday with "irreversible consequences" after a Russian man was killed by a shell fired across the border
Russia has promised to respond with "irreversible consequences" to a "dangerous escalation" of violence near its border, after a Russian man was killed and two women injured by shells fired across the Ukraine border.
Alexander Titov, a spokesman for the regional government in Rostov, told the Russian news agency Itar Tass that a shell damaged two homes at about 5.20am GMT in Donetsk, a town of the same name as the city in eastern Ukraine.
Rebel military leader Igor Strelkov was quoted as saying his forces had beaten off columns of government armour attacking from the south and west.
Pro-Ukrainian sources in the city of 425,000 people reported skirmishes.
At least 15 civilians were killed in Luhansk and the neighbouring Donetsk region on Sunday, reports say.
Germany and Russia have urged direct talks between Kiev and the rebels.
Meeting briefly in Rio de Janeiro before the World Cup final, German Chancellor Angela Merkel and Russian President Vladimir Putin called for the talks to be held by video link, Mrs Merkel's office said in a statement.
The two leaders agreed that the situation in Ukraine was "tending towards a deterioration", a Kremlin spokesman said.
The Russian town of Donetsk is near the border with Ukraine's Luhansk region, where Kiev-backed troops and pro-Russian separatists are fighting for the control of border checkpoints.
Grigory Karasin, Russia's deputy foreign minister, said the incident represented a "dangerous escalation for our citizens" and promised it "will not be left without a response", in televised remarks.
The Russian Foreign Ministry on Saturday warned Ukraine over what it says are continued attacks on its territory during the conflict, saying it "has the right to take measures to protect its territory and ensure the security of Russian citizens".
Ukraine has denied firing on Russian territory, and suggested the attack could have been the work of pro-Russian rebels trying to provoke Moscow to intervene on their behalf. The rebels denied they were responsible.
Andriy Lysenko, a spokesman for Ukraine's security council, was quoted by Interfax news agency as saying that Ukrainian forces "do not fire on the territory of a neighbouring country. They do not fire on residential areas".
He placed blame for the attack on the rebels, and condemned the shelling as a "provocation".
