People carried signs reading: "Stop Mass Spying," "Thank you, Edward Snowden" and "Unplug Big Brother" as they gathered at the foot of the Capitol to demonstrate against the online surveillance by the National Security Agency.
Estimates varied on the size of the march, with organizers saying more than 2,000 attended. U.S. Capitol Police said they do not typically provide estimates on the size of demonstrations.
The march attracted protesters from both ends of the political spectrum as liberal privacy advocates walked alongside members of the conservative Tea Party movement in opposition to what they say is unlawful government spying on Americans.
"I consider myself a conservative and no conservative wants their government collecting information on them and storing it and using it," said Michael Greene, one of the protesters.
"Over the past several months, we have learned so much about the abuses (of privacy) that are going on and the complete lack of oversight and the mass surveillance into every detail of our lives. And we need to tell Congress that they have to act," said another protester, Jennifer Wynne.
