"There is no excuse for the hateful statements that have been made and we condemn them unequivocally. We hope, however, that time and action, and the forgiving human spirit, will not result in the wholesale condemnation of an individual who we have otherwise known to be a decent person at core," the statement said.
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The tweet was sent from London on Sacco's account before she boarded a 10-hour-and-46-minute flight to Africa. The ordeal unfolded while she was in the air — on a Boeing 747 without Wi-Fi.
During that time, the hashtag #HasJustineLandedYet gained traction on Twitter, taking the top trending spot for hours.
Shortly after her flight landed, the Twitter account was deleted. Later, Sacco's Facebook account also was deleted.
On Friday night, IAC issued the following statement: "This is an outrageous, offensive comment that does not reflect the views and values of IAC. Unfortunately, the employee in question is unreachable on an international flight, but this is a very serious matter and we are taking appropriate action."
This wasn't the only tweet that raised eyebrows. Other tweets from Sacco's Twitter account included:
"I had a sex dream about an autistic kid last night. #fml" tweeted on Feb. 24, 2012, and "I can't be fired for things I say while intoxicated right?" tweeted on Jan. 30, 2013.
Sacco could not be reached for comment.