Linda Mack is a Canadian reporter who worked with Pierre Salinger at the London bureau of ABC News, specifically with the investigation of a terrorist bombing of a Boeing 747 over Scotland, which killed 270 people in 1988. Currently, she is a Wikipedia administrator under the name of SlimVirgin, as it was evidenced by Daniel Brandt of NameBase.org.
Brandt has written that:
"In the early 1990s, American journalist John K. Cooley worked with Pierre Salinger at the London bureau of ABC News, and was involved with the investigation of Lockerbie. In his email to Brandt, he described how they hired an impressive and energetic Linda Mack, who was eager to investigate the bombing. But after a while it became clear that Linda was trying to push journalists toward the official version of the story that accused Libya. It wasn't long before a special unit of Scotland Yard raided ABC News and seized certain materials. Because only a few people knew about the seized material, Salinger realized that this was the work of Linda Mack, and he locked her out of her office. ABC's efforts to fight the seizure were unsuccessful in court. Daniel Brandt had already announced the identification of SlimVirgin as Linda Mack publicly, and she knew that he was about to ask John Cooley for information. She called Cooley as a former colleague and asked him not to speak to Brandt. But her request was late — an email from Cooley to Brandt had already been sent."
Salinger, who was based in London, spent a considerable amount of time and energy investigating the bombing of Pan Am 103 over Lockerbie. "I know that these two Libyans had nothing to do with it. I know who did it and I know exactly why it was done," Salinger said during his testimony at the Zeist trial, where one of the Libyans was convicted of murdering the 270 victims.  Salinger later came to believe that Mack was actually working for Britain's MI5 on a mission to investigate the bombing and to infiltrate and monitor the news agency. This discovery comes only months after another Wikipedia admin --the infamous Essjay-- was caught lying about his credentials to the press. 
Despite the evidence, Wikipedia co-founder Jimbo Wales told the readers of the board Slashdot.org (who had published the story), the following statement:
"This story is demented and broken on so many levels, it is quite difficult to know where to begin, even. Here we have an excellent Wikipedia administrator who has been victimized by lunatic conspiracy theorists, a private person who has absolutely no relation to the wild stories that this article promulgates. Slashdot.org, you have been trolled."
As SlimVirgin in Wikipedia
Apparently, Mack went to live in Alberta, Canada, under the name of Sara McEwan. She joined Wikipedia on November 2004, and became an administrator in March 2005.  As SlimVirgin, Mack became a very efficient editor, with nearly 35,000 articles in her first year. The same SlimVirgin also holds a record of continuous editorial work lasting 26 hours. Some argue that these statistics from Wikipedia's editing records suggests either a supernatural ability, or that SlimVirgin is a convenient smoke screen for an entire team of specialists editing Wikipedia articles on behalf of intelligence services. Precisely, she had focused primarily on articles about Pierre Salinger and the doomed Pan Am 103 flight. SlimVirgin's editorial work progressed so well, and she observed (and abused) the rules so perfectly, that quickly she gained the rank of administrator. This gave her the right to remove "pesky" users from the debate and from editing.
Later on, Mack was voted the most abusive administrator of Wikipedia. She upset so many editors that some of them decided to team up to research her real life identity.
But attempts to track her through Internet technology failed. Once again, Brandt patiently assembled tiny clues about Slim Virgin and posted them on Wikipedia Review and Wikipedia-Watch.org. Eventually, two readers identified her. Slim Virgin was no other than Linda Mack, the young graduate Salinger hired.  Shortly after her Wikipedia identity was uncovered, many of her edits to articles related to the attack were permanently removed from the database in an attempt to conceal her identity.