Moscow: Moscow on Sunday vowed to respond to a "dangerous escalation" of violence near its border after authorities said a Russian man was killed by a shell fired from inside Ukraine
Russia said it has launched a probe to investigate the "murder" after a shell hit a residential area of the town of Donetsk, which lies next to the border with Ukraine`s restive east.
Deputy foreign minister Grigory Karasin said the incident represented a "dangerous escalation for our citizens" and vowed it "will not be left without a response," in televised remarks.
The small Russian town of Donetsk is near the border with Ukraine`s Lugansk region, where Kiev-backed troops and pro-Russian separatists are fighting for the control of border checkpoints.
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".
Kiev denies firing on Russian territory, blaming the shells on pro-Russian militants that still control much of the border area.
Rostov regional authorities spokesman Alexander Titov told Russian agencies an elderly woman was also injured when a shell hit a residential area of Donetsk on Sunday.
"Around 9:20 am (0520 GMT) a shell flew on the territory of Donetsk from Ukrainian territory. Two residential houses were damaged, one person died," he told Russian agencies.