Residential districts in the capital of South Ossetia, Georgia's breakaway republic, have come under heavy artillery fire, according to reports. Mortars and grenades are said to be being used. All of South Ossetia’s military have been placed on high alert

The shelling started at around 11 p.m., said Irina Gagloeva from the South Ossetian Committee for Information.

“We don’t know whether there are any casualties. The situation in the town is tense.  The shells are being fired at residential buildings and offices,” she said.

Meanwhile, throughout the day, Georgia tightened its military presence in the region, according to the head of the Joint Control Committee of Peacekeeping Forces, Marat Kulakhmetov. However, he said, it refused to monitor the area in question.

“For ten minutes the capital Tskhinvali came under heavy artillery gunfire which caused about ten or fifteen explosions across the city,” he said.

Earlier, according to reports, at least one person was killed, and two others injured when a South Ossetian police station came under fire from the Georgian village of Nuli.

South Ossetia declared independence from Georgia in the early nineties and a violent conflict followed. Peacekeepers from a Joint Control Commission have been stationed in the region since then.