President Trump firing off a number of tweets today in response to the special counsel headed by Robert Mueller.

FOX's Jon Decker has more from the White House:

In a string of messages on Twitter, President Trump confirmed he's under investigation by Special Counsel Robert Mueller and also appeared to criticize Deputy Attorney General Rod Rosenstein.

The President wrote, "I am being investigated for firing the FBI Director by the man who told me to fire the FBI Director! Witch Hunt."

Rosenstein's May memo critical of ex-FBI Director James Comey's performance was among the reasons cited by the President in Comey's firing. Soon after Comey's ouster, Rosenstein appointed Mueller to lead the investigation into Russia's interference in the 2016 presidential election.

At the White House, Jon Decker, FOX News.