Final answer:
During the Democratic National Convention in Chicago, hundreds of demonstrators were arrested by the police.
Step-by-step explanation:
During the protests at the Democratic National Convention in Chicago, thousands of demonstrators were arrested. The exact number is difficult to determine, but it is estimated that hundreds of protesters were arrested by the police during the event. This included prominent activists such as Abbie Hoffman and Jerry Rubin, who were later known as the 'Chicago Seven'.