Jesselyn Radack, whistleblower and director of the Government Accountability Project, speaks during the Stop Watching Us Rally protesting surveillance by the U.S. National Security Agency, on October 26, 2013, in front of the U.S. Capitol building in Washington, D.C.Allison Shelley/AFP/Getty Images
Thousands of protesters marched Saturday on Capitol Hill in Washington to protest against the National Security Agency's spying programs.
Saturday’s protest comes amid a widening scandal revealing sweeping U.S. surveillance on the communications of ordinary citizens and global leaders that has sparked outrage worldwide.
German spy chiefs will travel to the U.S. next week to demand answers following allegations that the NSA has been tapping Chancellor Angela Merkel's mobile phone.
The U.S. may have bugged Merkel's phone for more than 10 years, according to a report in German magainze Der Spiegel.
The news report on Saturday also said that President Barack Obama told the German leader he would have stopped it happening had he known about it.
The reports of bugging prompted Germany to summon the U.S. ambassador this week for the first time, an unprecedented post-war diplomatic rift.
Der Spiegel said Merkel's mobile telephone had been listed by the NSA's Special Collection Service (SCS) since 2002 -- marked as "GE Chancellor Merkel" -- and was still on the list weeks before Obama visited Berlin in June.
The furore has intensified after allegations that world leaders including the presidents of Brazil and Mexico have been among spying targets.
The protesters have been urging Congress to reform the legal framework supporting the secretive online data gathering since former NSA contractor Edward Snowden's disclosure of classified information about the programs, which are designed to gather intelligence about potential foreign threats.
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.
The event was organized by a coalition known as "Stop Watching Us" that consists of about 100 public advocacy groups and companies, including the American Civil Liberties Union, privacy group Electronic Frontier Foundation, Occupy Wall Street NYC and the Libertarian Party.
Exactly 12 years to the day after Congress passed the Patriot Act to expand anti-terror intelligence gathering in the wake of the September 11 attacks, the protesters called for an end to "mass spying."
The protesters handed to Congress an online petition signed by 575,000 people urging lawmakers to "reveal the full extent of the NSA's spying programs."
"It's not just Americans being caught in this dragnet. We need to stand up for the rest of the world too," Free Press media and technology advocacy group president and chief executive Craig Aaron told the crowd.
"It's not about right and left; it's about right and wrong."
Transparency in surveillance
The Obama administration and many lawmakers have defended the NSA programs as crucial in protecting U.S. national security and helping thwart past attack plots. They have also said the programs are carefully overseen by Congress and the courts.
In the wake of the scandal, Obama unveiled a series of measures in August to ensure more transparency in surveillance programmes, including the one that has most shocked the American public by collecting metadata from telephone records.
Congress plans to hold new hearings on the surveillance programs in the coming weeks and several bills are being drafted to amend the system.
The spying row has prompted European leaders to demand a new deal with Washington on intelligence gathering that would maintain an essential alliance while keeping the fight against terrorism on track.
Germany and Brazil are also working on a U.N. General Assembly resolution to highlight international anger at U.S. data snooping in other countries, diplomats said on Friday.
Al Jazeera and wire services