Acting General Services Administration chief Dan Tangherlini reprimanded organizers of a Las Vegas training conference in a video on Tuesday, calling their 2010 spending spree “completely unacceptable.”

“There were violations of travel rules, acquisition rules and good conduct,” Tangherlini said in a YouTube video posted on the GSA Web site. “Those responsible violated rules of common sense, the spirit of public service and the trust taxpayers have placed in all of us.”

Reports of the misdeeds have embarrassed the Obama administration and focused attention on the relatively little-known GSA, which manages all federal real estate and does most government purchasing.

Seven senior GSA leaders have been fired or placed on administrative leave pending further disciplinary action; Administrator Martha Johnson resigned under pressure last week hours before the report was released.

Four congressional hearings on the scandal are scheduled for next week.

One will be held by Sen. Claire McCaskill (D-Mo.), who said yesterday that several conference organizers received bonuses ranging from $500 to $1,500 for their contributions to the event. She is seeking a list of those officials from GSA.

Jeff Neely, the lead organizer and head of the San Francisco-based Pacific Rim office, received a bonus of approximately $9,000 for his performance in 2011, McCaskill said. The committee reviewing bonuses recommended against his getting one, but the advice was overruled by senior agency leaders, McCaskill said.

Tangherlini’s video came after Monday’s release of footage from the conference that showed GSA workers mocking the president’s clean energy campaign.

The clip, released by the chairman of the House Committee on Oversight and Government Reform, Darrell Issa (R-Ca.), shows a group of conference attendees promoting the “go green” campaign and singing to a gospel song.

“POTUS wants a press event, a project he can show,” the employees sing, while a worker holds up a portrait of Obama. POTUS stands for “president of the United States.”

The video was submitted for an awards competition at the conference.