"With all the weather, traveling across the Atlantic — it kind of pushed my plans back a little bit," Mackie continued.
In the caption of the post, event organizers promised to make it up to his fans.
"Fans who purchased autograph sessions and photo ops will be able to attain a refund or swap the ticket for another guest," the caption read.
Anthony is the third major star to withdraw from the festival. Aquaman star Jason Momoa and Star Trek and Battlestar Galactica actor Rick Worthy previously cancelled their appearances as well.
Comic Con Africa takes place today through Sunday at the Kyalami Grand Prix and International Convention Centre. Other stars set to appear include The Big Bang Theory’s Kevin Sussman and American Gods star Demore Barnes.
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