Moldova's pro-Russian breakaway region of Transnistria said on Wednesday that shots were fired from the territory of Ukraine overnight towards a village that houses a large ammunition depot.
The region’s interior ministry also said that it had detected drones that it said were launched from Ukraine.
It comes after Moldova raised its terrorist threat level on Tuesday and the Kremlin voiced serious concerns as two blasts damaged Soviet-era radio masts in the breakaway region of Transnistria where authorities said a military unit was also targeted.
Russia has had troops permanently based in Transnistria since the collapse of the Soviet Union. Kyiv fears the region could be used as a launchpad for new attacks on Ukraine, while there are concerns of the situation leading to a wider conflict across Europe.
Moldova’s president Maia Sandu said on Tuesday that the series of attacks were an attempt by factions within the territory to increase tensions.
“From the information we have at this moment, these escalation attempts stem from factions from within the Transdniestrian region who are pro-war forces and interested in destabilising the situation in the region,” Ms Saudu told a news conference after Moldova’s Security Council held an urgent meeting.
No residents were hurt in the explosions, but two radio antennae that broadcast Russian radio were knocked out, Transnistria’s interior ministry said.
Kremlin spokesman Dmitry Peskov told reporters the news was a cause for serious concern and that Russia was following events closely while Kyiv accused Moscow of trying to drag Moldova into the conflict.
The southern Ukraine coastline and Moldova have been on edge since a senior Russian military officer said last week that the Kremlin's goal is to secure not just eastern Ukraine but the entire south, so as to open the way to Transnistria, a long, narrow strip of land with about 470,000 people along the Ukrainian border where about 1,500 Russian troops are based.
It was not clear who was behind the blasts in Transnistria, but the attacks gave rise to fears that Russia is stirring up trouble so as to create a pretext to launching further attacks on Ukraine.
The incident will not help mounting tensions in the relationship between Russia and the west over the conflict in Ukraine.
Russia’s foreign minister Sergei Lavrov said on Tuesday the Kremlin is ‘effectively’ at war with Nato for supplying weapons to Ukraine. Mr Lavrov said weapons supplied by Western countries "will be a legitimate target", adding that Russian forces had already hit weapons warehouses in western Ukraine.
"Everyone is reciting incantations that in no case can we allow World War Three," Mr Lavrov said in a wide-ranging interview on Russian television. He accused Ukrainian leaders of provoking Russia by asking NATO to become involved in the conflict.
Mr Lavrov went on: "NATO, in essence, is engaged in a war with Russia through a proxy and is arming that proxy.
"War means war."