Savannah Guthrie apologizes after swearing on-air

June 29, 2012. Savannah Guthrie co-hosts NBC's "Today" show in New York. (Reuters)

Savannah Guthrie apologized to fans after the "Today" host accidentally cursed during a live show.

Guthrie didn't realize the cameras were on her when she was practicing her segment. She let out the curse word before she was informed she was on-air.

"Oh s--t," Guthrie said not realizing her mic was on during Wednesday's live show. She quickly apologized for her outburst.

She later joked about the gaffe on Twitter.

"Check, check -- is this thing on? Yeah I guess it is," she wrote. "So sorry guys. Thanks for being kind and understanding. And guess it’s good thing I don’t wear a mic all day. #ohdarn."

Viewers took to Twitter to laugh at the anchor's slip-up.

"Did she say, "S--t!" on the air, or was that just Savannah Guthrie?! Hahahaha...." a viewer tweeted.

"99% sure that Savannah Guthrie just said “oh s--t” on live TV," one user wrote.

Another chimed in, "Savannah Guthrie just said s--t on live tv. 😂😂😂."