Trump said he couldn't believe the network was "wasting airtime on Mayor Pete, as Chris Wallace likes to call him."
Brit Hume of Fox News responded by tweeting that at least Buttigieg was "willing to be questioned by Chris Wallace, something you've barely done since you've been president. Oh, and covering candidates of both parties is part of the job of a news channel."
In addition to attacking Fox News for its Buttigieg special, the president also tweeted twice about his own interview, also on Fox News, that was airing at the time.
Here's a short clip of Buttigieg that was posted to his Twitter feed:
Buttigieg, a 37-year-old voted "most likely to be president" as a high school senior, speaks a half-dozen languages, graduated from Harvard, was a Rhodes Scholar at Oxford and served in Afghanistan with the Navy Reserve.