Over one hundred thousand protesters poured into Independence Square, joining thousands who've been camping there.
Organizers and opposition leaders are doing their best to maintain peace, but the protests have come increasingly closer to violence as anger continues to mount.
Police used water cannons against protesters who moved on the parliament and other government buildings.
During Sunday, thirty police were hurt and at least fifty protesters were injured.
Anger increased greatly after parliament passed a heavily controversial law, on Friday.
Under the bill, any protest can be banned, freedom of speech is limited, freedom of the press is cut, the government is allowed to ban citizens from using the internet, and it classifies advocacy groups as "foreign agents" if they receive money from abroad.
Opposition leaders accused Yanukovych of trying to cement a dictatorship by following the ways of Russia and North Korea.
News of the bills passing was met with condemnation from much of the world, especially the EU.
Continuous protests have been taking place in Kiev, and elsewhere in Ukraine, for several months now,with crowds as large as two hundred thousand, in Kiev's Independence Square alone.
Many Ukrainians worry that Yanukovych is taking their country back under Russian influence and fear a loss of their independence from their former Soviet masters.
The protests gained steam after three former presidents backed them.
Police were unable to clear out the protesters in December, and their failure had been followed by Yanukovych promising to get back to working on the deal with the EU.
However, his once again breaking his word has only heightened the calls for his removal from office and led to many to call him a traitor and warn that he should never return to the country.
The opposition had called for the government to replace him, but their lack of movement on the issue has led to calls for their removal as well.
