UPDATE: Justine Sacco has issued the following written apology to South African newspaper The Star, according to ABC News:

"Words cannot express how sorry I am, and how necessary it is for me to apologize to the people of South Africa, who I have offended due to a needless and careless tweet. There is an AIDS crisis taking place in this country, that we read about in America, but do not live with or face on a continuous basis. Unfortunately, it is terribly easy to be cavalier about an epidemic that one has never witnessed firsthand.

"For being insensitive to this crisis—which does not discriminate by race, gender or sexual orientation, but which terrifies us all uniformly—and to the millions of people living with the virus, I am ashamed.

"This is my father's country, and I was born here. I cherish my ties to South Africa and my frequent visits, but I am in anguish knowing that my remarks have caused pain to so many people here; my family, friends and fellow South Africans. I am very sorry for the pain I caused."

Original item below:

Website parent company IAC, owner of Match.com, Vimeo and many other popular services, announced today it has fired PR chief Justine Sacco for her instantly infamous tweet about AIDS in Africa.

"The offensive comment does not reflect the views and values of IAC. We take this issue very seriously, and we have parted ways with the employee in question," the company said in a statement emailed to journalists.

"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 whirlwind story of a successful PR pro's downfall on a global social media stage unfolded in little more than 24 hours. Sacco's tweet—"Going to Africa. Hope I don't get AIDS. Just kidding. I'm white!"—was posted shortly before she boarded a flight, leaving her likely unaware of the worldwide consternation and mockery she had instigated.