Did the communists in the Soviet Union also accuse their political enemies of racism and violence to silence their voice?

The Soviet Union was never communist. Not even close. It was much closer to a dictatorship.

Yes...........................

No, they just "Locked them Up!" 

They definitely did!  They also called everyone from social democrats to monarchists, "fascists", and themselves as of course the virtuous "anti-fascists", justifying violence.  Look at modern-day Antifa.  If it quacks like a duck...

“Socialism itself can hope to exist only for brief periods here and there, and then only through the exercise of the extremest terrorism. For this reason it is secretly preparing itself for rule through fear and is driving the word ‘justice’ into the heads of the half-educated masses like a nail so as to rob them of their reason… and to create in them a good conscience for the evil game they are to play.”

― Friedrich Nietzsche, 1878

Yes. They accused them of being counter revolutionaries and enemies of the state to oppose their socialist hellholes 

They used false accusations of crime, sending political opponents to prison.

Stalin was fond of saying "Lock Her UP!"

No, they just cut to the chase and imprisoned or shot dissenters. I can imagine there’s a lot of communist Americans that wish they could follow suit. 

Not racism.  They were accused of not having the communist mindset.  Which could get you shot.

Today, Vlad. just poisons his opposition.

Yugoslavia was easy breakup.