"Manu, you're a liberal hack. I'm not going to talk to you," McSally said before cutting into a side room. Raju had asked McSallly whether the Senate should consider new evidence as part of the impeachment trial.
It's unclear what exactly prompted McSally's barb but it was leveled at a news network regularly panned by Republicans for showing liberal bias.
After Raju tweeted about the incident, McSally doubled down and tweeted her own video of the exchange.
Raju also seemed to indicate McSally's comments stemmed from the fact that she faced a difficult election in Arizona.
"Sen. Martha McSally, a Republican facing a difficult election race, lashed out when I asked if she would consider new evidence as part of the Senate trial," she said.
According to The Washington Post, CNN said it was “extremely unbecoming for a U.S. Senator to sink to this level and treat a member of the press this way for simply doing his job.”
McSally's office did not immediately respond to Fox News' request for comment. On Twitter, the reactions were mixed. Some defended McSally while others criticized her.
McSally and Raju's exchange came as the Senate prepared to hold a trial over House Democrats' articles of impeachment. On Wednesday, House Speaker Nancy Pelosi, D-Calif., announced several managers who would present the case to McSally's chamber.
While the Senate is expected to reject any attempt to remove President Trump from office, the trial could put a spotlight on senators like McSally who represent purple states.
Pelosi was initially reluctant to transmit the impeachment articles to the Senate, citing Republican leadership's cooperation with the White House. Democrats have also conflicted with Republicans over introducing new evidence and witnesses during the trial.