The criticism comes in an email from Swedish ambassador Sven-Olof Petersson to Elizabeth Farrelly in response to an April 12th column entitled "Truth of Assange is stranger than fiction" in the Sydney Morning Herald (SMH).
Petersson offers a sarcastic thanks to Farrelly for her defence of Assange in the column.
“It is good to get this straightened out from someone who clearly was present during the 'penetrations'!” Petersson wrote in one of a series of emails published by WikiLeaks on Sunday.
Petersson also branded the newspaper "sad" for editing his response to her piece.
“The way you choose to cut down my letter sends a strong signal that while your columnists are free to write any kind of rubbish, you will not allow those effected (sic) to criticize your columnists!” he wrote in an email to editor Antony Lawes.
Petersson also told colleagues in Sweden that SMH had “mutilated” the adjoining headline.
Wikileaks’ Twitter account published a link to more than 100 pages worth of documents on Sunday and immediately faced flack on the social media site for choosing to describe Petersson’s reaction as “going berserk”.
“Berserk? I'm afraid you lost me. This kind of tabloid biased rubbish i did not expect from you,” one follower tweeted.
Another follower drew attention to the fact that the Swedish government had acted in accordance to transparency law by handing over the documents.
Assange is wanted for questioning over rape and sexual assault allegations made against him by two Swedish women in 2010.
He is currently living in Ecuador's embassy in London in an ongoing bid to avoid extradition to Sweden.
He has repeatedly cited fears that Sweden will send him on to the USA.
Sweden's ambassador also addressed those fears in his comment published in the Sydney Morning Herald, in which he details extradition law.
"A person risking the death penalty can not be extradited. Nor can a person be extradited for 'political' or 'military' offences," the ambassador wrote.
The documents also include several emails from members of the public, many of which criticize Foreign Minister Carl Bildt for his handling of the Assange case.
The docket also contains official reports from Swedish embassy officials across the work about how local media reports about Sweden and the Assange case.
Swedish Foreign Ministry spokesman Anders Jörle downplayed the significance of the documents' release.
"We're the ones who made these documents public," he told The Local.
All official documents that are not classified can be obtained by members of the public in Sweden (offentlighetsprincipen), he underlined.
"We are not biting our nails over this and I see no reason to review how the ambassador reacted to the media reports," Anders Jörle told The Local.
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