Russian forces entered Ukraine on Thursday after President Vladimir Putin ordered a military operation in the eastern region of the country where Russia earlier recognised two new republics.
Quoting Ukraine, Reuters reported that missiles hit Ukrainian cities after Russian troops enter the borders from Russia and Belarus.
Russia, however, denied firing rockets, bombs or shells on Ukrainian cities.
The country’s defense ministry spokesman Igor Konashenkov told the media on Thursday, "Russia’s armed forces carry out no missile, air or artillery strikes against Ukrainian cities."
An adviser to Ukraine presidential office said their troops fought Russian forces along practically the entire border, and fierce fighting was taking place in the regions of Sumy, Kharkiv, Kherson, Odessa and at a military airport near Kyiv.
Explosions were heard before dawn and throughout the morning in the capital Kyiv, a city of 3 million people. Gunfire rattled, sirens blared, and the highway out of the city choked with traffic as residents fled.
Konashenkov, however, said Ukrainian border guards offered no resistance to Russian forces and according to the available intelligence Ukrainian soldiers were massively vacating positions and leaving weapons.
He stressed that the positions of Ukrainian military units that had agreed to lay down arms were not being attacked, while Russian smart weapons were being used to eliminate military infrastructures, air defense facilities, airdromes and aircraft.
