Religious groups are demanding an explanation from NBC for omitting the words "under God" from a segment featuring the Pledge of Allegiance that aired Sunday before the live telecast of the U.S. Open.

NBC has issued two apologies so far.

The live broadcast began with a video of children reciting the oath. The word "under God" was edited out, not just once, but twice.

Viewers immediately noticed the editing and started posting complaints on the social networking websites Facebook and Twitter.

Later during the broadcast, NBC apologized for the omission saying the network didn't intend to offend anyone.

NBC Sports also issued a written apology on Monday concerning the incident, calling it a "bad decision."