Washington (CNN) Republican front-runner Donald Trump on Wednesday tried something new on Twitter: defending another presidential candidate.

Trump took to his favorite social medium to show support for fellow GOP presidential hopeful Ben Carson, who has been criticized for saying Tuesday that he would have confronted the gunman who killed nine people at an Oregon community college last week and "not just stand there and let him shoot me."

"Ben Carson was speaking in general terms as to what he would do if confronted with a gunman, and was not criticizing the victims. Not fair!" Trump tweeted Wednesday morning.

The tactic is a new one for Trump, who has often used Twitter to attack his competitors -- including Carson --- for the Republican nomination.

The Trump defense comes as Carson has surged to second place in some polls behind Trump, who continues to lead the GOP pack.

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