At least seven people, including a 23-day-old child, were killed as Russian shells hit southern Ukraine on Sunday.

Apart from the baby, his 12-year-old brother and their parents also died in the shelling.

Bombs hit their family home in the village of Shyroka Balka in Kherson, Interior Minister Igor Klymenko was quoted as saying by BBC.

"Terrorists must be stopped. They must be stopped by force," Klymenko said.

"They don't understand anything else," the Minister said.

Kherson is one of the four regions of the war-hit country which Russian President Vladimir Putin claimed to have annexed last year.

Ukraine's military reclaimed the western part of the region last November but Russian troops have continued to shell the area from across the Dnipro river, reports BBC.

Meanwhile, the Ukrainian military is strengthening a second line of defense in the Rivne Region near the border with Belarus, filling it with traps against infantry and vehicles as well as planting mines near the Rivne nuclear power plant, Ukrainian media reported on Saturday.

There is no visible threat from Belarus at the moment, but the density of minefields is being increased to be ready for any development, the Channel 5 broadcaster reported as quoted by Xinhua.