Railing against “tax breaks for billionaires” and issuing a warning to Pennsylvania lawmakers, Sen. Bernie Sanders delivered a firebrand speech Thursday afternoon to a crowd clustered outside City Hall.

After Sanders’s speech, protesters marched throughout the city and, in some instances, ignored requests by local police to clear the way for rush hour traffic.

More than 70 demonstrators were arrested in Philadelphia for blocking a highway during a May Day rally that included Sen. Bernie Sanders, who joined local labor unions and activists to protest various issues.