KIEV, Ukraine (AP) -- As many as 100,000 demonstrators chased away police to rally in the center of Ukraine's capital on Sunday, defying a government ban on protests on Independence Square, in the biggest show of anger over the president's refusal to sign an agreement with the European Union.

Chants of "revolution" resounded across a sea of EU and Ukrainian flags on the square, where the government had prohibited rallies starting Sunday.

The crowd was by far the largest since the protests began more than a week ago. Many of the demonstrators had traveled to Kiev from western Ukraine, where pro-EU sentiment is particularly strong.

"We are furious," said Mykola Sapronov, a 62-year-old retired businessman. "The leaders must resign. We want Europe and freedom."

Protests have been held daily in Kiev for more than a week after President Viktor Yanukovych backed away from an agreement that would have established free trade and deepened political cooperation between Ukraine and the EU. He justified the decision by saying that Ukraine could not afford to break trade ties with Russia.

The EU agreement was to have been signed Friday and since then the protests have gained strength.

Sunday's demonstration also was energized by anger over the violent dispersal of several hundred protesters at Independence Square early Saturday. Some of the protesters were bleeding from their heads and arms after riot police beat them with truncheons.

As the vast column of demonstrators approached the square on Sunday and removed metal barriers blocking it off, all police left the square.