Authorities in Kyiv have accused Moscow of provoking a deadly gunfight between pro-Russian and pro-Ukrainian activists in the eastern city of Kharkiv
At least two men were killed and five others wounded in the overnight clashes.
Rival groups both blamed each other for the violence, with Ukrainian authorities saying they feared Russia might use the trouble as a pretext to invade.
Accusing pro-Russian provocateurs, Ukraine’s interior minister Arsen Avakov urged people via social media not to fight back.
The killings in Kharkiv follow Thursday’s fatal clashes between demonstrators in Donetsk, which saw one man die and came as Ukraine’s acting president also claimed Russian troops had massed on the country’s eastern border and were “ready to invade at any time”.
But, pro-Russian activists say far-right extremists are behind the violent unrest inside Ukraine.
Russia’s foreign ministry also insisted on Friday no invasion plan of Ukraine exists.
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