Justine Sacco, head of corporate communications for IAC, a media company Diller that operates websites like The Daily Beast, About.com, CollegeHumor and Match.com., received thousands of harsh replies directed at her tweet that said, Going to Africa. Hope I don't get AIDS. Just kidding. I'm White!," according to CNN.

Sacco was in London when she wrote the message on the microblogging site and about to embark on a long vacation in South Africa. Her tweet went viral over the Internet while she was still on a 12-hour flight going to Cape Town, South Africa, the report said.

With less than 600 followers on Twitter, Sacco's Twitter account soon had thousands of followers after websites like Valleywag and Buzzfeed highlighted her tweet. Her account was filled with harsh comments, some hateful, while others said they felt sorry for her because Sacco didn't get the chance to defend herself while in flight.

Many Twitter users who scanned through Sacco's previous public posts were disturbed by the messages they read. According to CNN, Sacco's account was a long list of "banal complaints about poor customer service and other apparent indignities." On one post, Sacco even tweeted "I had a sex dream about an autistic kid last night."

"It seems she has left a trail of casual racism across social media on her various travels," Chris Taylor, a writer for Mashable, said.

A corporate communications representative for IAC issued a statement Friday afternoon even before Sacco's plane had landed in South Africa.

"This is an outrageous, offensive comment that does not reflect the views and values of IAC,' the company said in a statement. "Unfortunately, the employee in question is unreachable on an international flight, but this is a very serious matter and we are taking appropriate action."

The statement led to speculations whether Sacco will be reprimanded or terminated.