The Israeli Defense Force has issued a "clarification" admitting it manipulated audio of its raid on a Gaza-bound aid flotilla.

On Friday, the IDF released audio of what it said was an exchange between Israel Navy officers and the crew of the Mavi Marmara, the main vessel in the flotilla. In it, voices could be heard telling the Israeli soldiers to "go back to Auschwitz" and "we're helping Arabs go against the US -- don't forget 9/11, guys."

But flotilla passengers quickly began disputing the veracity of the audio clip.

Investigative journalist Max Blumenthal reports that the head of the Free Gaza movement, Huwaida Arraf, could be heard on the videotape asserting the flotilla's right to enter Gaza territory. But Arraf says she wasn't on board the Mavi Marmara, and was actually on board another ship, the Challenger One. Another flotilla member whose voice can be heard on the audio, Ali Abunimah, also said he wasn't aboard the Mavi Marmara.

According to a news report from the Palestinian news agency Ma'an, Arraf suggests the audio of her that appeared in the clip came from an earlier exchange between her and Israeli forces, but she admits she "could not be sure" she didn't repeat her assertion during exchanges with the IDF during the raid.

On Saturday, the IDF's public blog issued a "correction" explaining that the tape had been edited "so as to make it easier for people to listen to the exchange."

The IDF stated:

There have been questions regarding the authenticity of the recording as well as its attribution to a communication with the Mavi Marmara.

So to clarify: the audio was edited down to cut out periods of silence over the radio as well as incomprehensible comments so as to make it easier for people to listen to the exchange. We have now uploaded the entire segment of 5 minutes and 58 seconds in which the exchange took place and the comments were made.

This transmission had originally cited the Mavi Marmara ship as being the source of these remarks, however, due to an open channel, the specific ship or ships in the “Freedom Flotilla” responding to the Israeli Navy could not be identified.

The IDF's latest version of the audio is actually the third version the military organization has released. Its first audio version of the incident, a one-minute clip released the day of the raid, did not include any of the controversial comments -- no voices can be heard saying "Go back to Auschwitz" or "remember 9/11."

Critics of Israel have suggested the audio clip -- and the IDF's admission it was edited -- shows the Israeli military is involved in a propaganda campaign to discredit the flotilla as a humanitarian effort. And Blumenthal notes that the IDF audio has already made its way into US media as fact.

"Hours after the IDF’s admission, major news outlets which reported on the doctored audio clip as though it was a shocking revelation and not a scandalous forgery have still not corrected themselves," Blumenthal writes.

Some of Israel's other efforts to sway public opinion its way have resulted in embarrassment. Government spokesmen on Saturday apologized for distributing a video that mocked the flotilla members, nine of whom died when Israeli commandos raided the flotilla on Monday.

The video, a satire on "We are the World," shows a group of singers declaring, "There's no people dying/So the best that we can do/Is create the greatest bluff of all/We must go on pretending day by day that in Gaza/There's crisis hunger and plague."

Following a storm of protests from critics pointing out that the UN has declared that Gaza is in the midst of a humanitarian crisis, the Israeli Government Press Office declared, "Due to a misunderstanding on our part, earlier (Friday) we inadvertently issued a video link that had been sent for our perusal. ... It was not intended for general release. The contents of the video in no way represent the official policy of either the Government Press Office or of the State of Israel."

The following audio is the original clip released by the Israeli Defense Force on May 31, 2010. It does not include any of the inflammatory comments heard in later versions.