The situation is tense in Kharkiv on the Ukrainian side of the border with Russia.
Witnesses in the north eastern city claim to have seen armoured vehicles and other military equipment being used in the neighbouring country.
Reports suggest a pro-Russian militant group is planning to hold its own breakaway referendum in the area.
Euronews’ correspondent in Kharkiv, Angelina Kariakina says:
“Russian territory is just over this border-line. From here in Ukraine, we can’t see any Russian troops, or military equipment at the moment. However, Ukrainian border guards continue to work under heightened security. Every day they refuse entrance to dozens of people who they suspect of planning to take part in, or provoke, conflict on Ukranian territory.”
Ukrainian border official, Oleksandr Moskvyn, listed some of the items his colleagues have reportedly confiscated.
“People we’ve detained had knives, tear-gas spray and gloves used by police special units,” he said.
Clashes on Friday between pro-Ukrainian and pro-Russian activists in Kharkiv city have prompted local officials to issue an appeal for calm over the weekend.
But not everybody thinks the tension on the border will result in violence.
“Some families here are split,” said one Ukrainian man travelling back from Russia. “Me, for example. I live in Ukraine and my children live both in Russia and in Ukraine. Is it really possible that someone will come from Russia to shoot me here? Or that I could go to Russia and shoot someone there?”
The Russian Ministry of Defence says military training is underway close to the border and will continue until the end of March.
But the Ukrainian guards in Kharkiv seem to be taking no chances.