Anti-choice campaigner Troy Newman has been blocked from entering Australia after online petitions and a last-minute government intervention.
According to a video he posted to Facebook, Newman was pulled off his flight in Denver and told he could not travel to Los Angeles, where his flight to Melbourne would be departing.
Newman - who was engaged to speak at a Right To Life convention this week - wrote in his post that the Australian government had revoked his visa "in midflight".
"It is clear that the pro-abortion crowd does not want anyone to hear the truth about Planned Parenthood's illegal actions," he wrote.
"Please pray for me I'm stuck in Denver airport like a man without a country."
The move comes after the public was alerted to Newman's upcoming speaking tour of Australia - and his record of anti-choice extremism - following the ban on rapper Chris Brown earlier this week.
Newman's organisation 'Operation Rescue' is responsible for spreading damaging misinformation about American reproductive health providers Planned Parenthood, and it has also been linked to the execution of a doctor who provided women with late-term abortions.
A change.org petition with over 2,500 signatures, and a letter-writing campaign to politicians, appears to have paid off, with Immigration Minister Peter Dutton confirming this afternoon that Newman's visa has been cancelled.
Newman has the right to appeal the decision, but any reversal is unlikely to take place in time for his scheduled speaking date on Friday.
CORRECTION: An earlier version of this article wrongly attributed an anti-abortion stance to the group Collective Shout. Fairfax Media accepts Collective Shout has never had a position on abortion.