MOSCOW: Moscow is considering targeted strikes against Ukraine after a shell reportedly crossed the border and killed a Russian civilian, the Kommersant daily reported Monday, citing a source close to the Kremlin.

The daily quoted a source as saying that Moscow was considering the possibility of “targeted retaliatory strikes” against Ukraine, where escalating clashes between pro-Moscow rebels and government troops threatened to spiral into an all-out civil war over the weekend.

“Our patience is not limitless,” the source was quoted as saying, adding that Russia “knows exactly where [Ukrainians] are firing from“. The source said that Russia was not considering any large-scale action, but only targeted one-off strikes on positions from which fire is directed at Russian territory.

Moscow said Sunday that a Ukrainian shell had landed in Russia and killed a civilian, prompting the Russian foreign ministry to say that the incident was “another act of aggression” that could have “irreversible consequences“. Ukraine denied the claim, saying that government forces “had never before, are not now, and never will fire on the territory of a neighbouring state”.

Several shells landed early Sunday in the small Russian border town of Donetsk, which has the same name as rebels' stronghold city in eastern Ukraine, killing one resident and wounding two.

The deputy speaker of Russia's upper house of parliament, Yevgeny Bushmin, said Sunday: “We need to use targeted weapons, like Israel does among others, to destroy those who launched this mine.“