A day after its social media agency fired an employee who posted an obscenity on Chrysler's official Twitter account, the automaker severed its relationship with the firm.

It is the latest example of what is expected to become a growing challenge, as companies increasingly use social media to communicate with consumers, partners, and the press and, frequently giving authority over these missives to individuals in various internal departments and third-party marketing organizations. Whether done by mistake -- as apparently was the case here, when the agency rep erroneously posted a personal tweet to the Chrysler account -- or with malice, an individual easily can post tweets or Facebook messages damaging to a product's brand or company's image.

The auto industry is heavily vested in social media: 73% of light-vehicle brands have at least one Facebook page, 70% have a YouTube channel, and 60% use a Twitter account, according to a 2010 L2 Digital IQ study.

The tweet appeared under ChryslerAuto on Wednesday morning, but was written by a now former employee at New Media Strategies. On Thursday, Chrysler said it will not renew its contract with the agency; instead, it will move into a transition period while it searches for a replacement social-media marketing firm.

"Chrysler Group LLC will not renew its contract with New Media Strategies (NMS) for the remainder of 2011. NMS has agreed to support us with an orderly transition until a new agency has been named. We thank them for the work they have provided to us and wish them the best as they move forward," said Chrysler, in a statement .

New Media Strategies posted a statement, stating its regret about the "unfortunate incident."

NMS CEO Pete Sndyer said in a company blog that the incident "certainly doesn't accurately reflect the overall high-quality work we have produced for Chrysler. We respect their decision and will work with them to ensure an effective transition of this business going forward."

Chrysler did not ask New Media Strategies to fire the employee who posted the tweet: "I find it ironic that Detroit is known as the #motorcity and yet no one here knows how to f***ing drive."

But the company was offended by the tweet's spelled-out obscenity and the poster's denigration of Detroit's drivers, which went against Chrysler's new ad campaign that promotes the city, wrote Ed Garsten, Chrysler manager of electronic communications, in a company blog on Thursday. Although some bloggers and online commentators criticized Chrysler for overreacting, the automaker was not overly sensitive, given the success of its recently launched commercial and marketing campaign, he said.

"This company is committed to promoting Detroit and its hard-working people. The reaction to that commercial, the catchphrase 'Imported from Detroit,' and the overall positive messages it sent has been volcanic," Garsten wrote. "Inside Detroit, citizens are becoming even more proud of their town, and outside the region, perception of Detroit is rapidly improving. With so much goodwill built up over a very short time, we can't afford to backslide now and jeopardize this progress. We need to keep the momentum going -- rebuilding a region and an industry, and not let anything slow us down. It's what we do."

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