(CNN) -- Congressional investigators are accusing the General Services Administration of violating its employee gift limit with rewards of iPods, digital cameras and other electronics, just as a video emerged of a lavish conference that shows employees drinking and making jokes about wasteful spending.
The video, first obtained by The Huffington Post on Friday, offered a glimpse inside the agency's $820,000 conference in Las Vegas. An administration official confirmed the authenticity of the video and provided a copy to CNN.
Reports of the lavish conference have prompted taxpayer outrage, embarrassed the administration and put a spotlight on the wasteful spending by the agency that acts as a real estate agency for the federal government.
"These videos reinforce once again the complete lack of judgment exhibited during the 2010 Western Regions Conference," said Greg Mecher, a GSA spokesman. "Our agency continues to be appalled by this indefensible behavior, and we are taking every step possible to ensure that nothing like this ever happens again."
The latest news comes just days after the Office of the Inspector General documented massive overspending by the GSA. The fallout from the report's revelations has sparked a congressional investigation and seen the GSA chief step down, two other employees fired and a number of others suspended.
On Friday, Republican investigators for the House Transportation and Infrastructure Committee said the GSA's Public Buildings Service developed an employee incentive program known as the "Hats Off Store" that spent nearly $500,000 on gifts -- from iPods to GPS devices -- that vastly exceeded its $99 per-gift limit.
They also said accounting for the gifts as well as the justification for giving them were lacking or inconsistent, according to a statement released by Rep. Jeff Denham, R-California, chairman of the Subcommittee on Economic Development, and Rep. John Mica, R-Florida, chairman of the transportation committee.
While the investigation found the GSA's massive spending began in 2007 under the Bush administration and continued under the current leadership, Republican congressmen leading the investigation have hammered President Barack Obama over the allegations.
"More and more information is coming out about the total lack of accountability and outrageous spending habits of the General Services Administration," Denham said in the statement.
Denham accused the administration of treating taxpayer dollars "like their own private slush fund."
Meanwhile, House Oversight Chairman Darrell Issa, R-California, has accused the White House of sitting on the IG's findings about the GSA for 11 months. The administration has dismissed Issa's claims, saying the investigation followed proper procedures.
The allegations Friday by Denham and Mica, and the video are likely to inflame the political divide.
The video shows employees at the GSA's 2010 Western Regions Conference in Las Vegas putting on magic shows and singing Frank Sinatra songs.
In one clip, a person dressed as a clown talks about making work more difficult for others.
"Government, if you think the problems we create are bad, just wait until you see our solutions," the clown warns the audience.
The reports of overspending have prompted a bipartisan reaction, with Sen. Barbara Boxer, D-California, the chair of the Senate Environment and Public Works Committee, saying she will hold hearings on the GSA findings next week.
CNN's Dana Bash, Brianna Keilar and Deirdre Walsh contributed to this report.