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Republican National Committee Chairman Reince Priebus says he will continue to fight against attacks on his party after he received an apology from MSNBC’s big boss over a tweet by the network that accused conservatives of animosity toward biracial families.

The cable network's President Phil Griffin "personally" apologized and said at least one head rolled after the channel's latest misstep. On Wednesday, MSNBC's official Twitter account sought to politicize a Cheerios commercial featuring a biracial family that debuted months ago and is slated to air in a new version during the Super Bowl.

"Maybe the rightwing will hate it, but everyone else will go awww: the adorable new #Cheerios ad w/ biracial family,” the tweet read.

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Priebus told Fox News’ Sean Hannity Thursday that Griffin’s mea culpa is a “first step” for the network, but he will not stand for such attacks to continue.

“Now we have to stay on top of it,” he said. “You know what, it’s sort of like being on probation I guess, but the fact of the matter is we’re here, we’re watching them and it’s our responsibility and it’s mine in particular also to stand up for our party.”

After the tweet was posted, Priebus wrote a letter to Griffin demanding he "personally and publicly" apologize, and stating that until he did, all RNC personnel would be banned from appearing on the channel's shows. Hours later, Griffin obliged.

"The tweet last night was outrageous and unacceptable," Griffin said in a statement. "We immediately acknowledged that it was offensive and wrong, apologized, and deleted it. We have dismissed the person responsible for the tweet.

"I personally apologize to Mr. Priebus and to everyone offended," he continued. "At MSNBC we believe in passionate, strong debate about the issues and we invite voices from all sides to participate. That will never change."

Griffin did not say who was fired for the Tweet.

The Tweet prompted an angry tide of reaction from conservatives, many of whom noted their own families spanned races, either through marriage or adoption. Most wondered why the left-wing news network thought it was such a big deal.

Conservative commentator Michelle Malkin went on Twitter and urged her followers to send photos of their own biracial families to MSNBC’s Twitter feed with the hashtag “#MyRightWingBiracialFamily.”

The network quickly issued an impersonal apology for the Tweet and took it off its official feed.

A second Twitter missive announced the offensive tweet had been deleted and included another apology.

MSNBC wrote of a “backlash” against the commercial in June of last year, using random comments posted under a YouTube video to make the case that conservatives were angry about it. In the article, Christopher Colbert, the African-American father of the 6-year-old Grace, who stars in the ad, said he welcomed any national debate spurred by his daughter’s role.

Priebus said in his letter to Griffin the misguided Tweet is part of a "pattern of behavior" that has "poisoned" the network.

"Sadly, such petty and demeaning attacks have become a pattern at your network," Priebus wrote in a Jan. 30 letter to Griffin. "With increasing frequency, many of your hosts have personally denigrated and demeaned Americans -- especially conservative and Republican Americans -- without even attempting to further meaningful political dialogue."

The latest flap arose just weeks after MSNBC personality Melissa Harris-Perry apologized on air for leading a panel discussion that mocked former Republican presidential candidate Mitt Romney for having an adopted black grandson.

In November, then-MSNBC host Martin Bashir created a racial controversy when he blasted one-time Alaska governor and GOP vice presidential nominee Sarah Palin for comparing the effect of the ballooning national debt on Americans to slavery. Bashir described a vile punishment for slaves and suggested someone perform the act on Palin. Bashir was suspended more than two weeks later, and resigned on Dec. 4, 2013.

Days before Bashir’s outrageous gaffe, actor Alec Baldwin, host of a short-lived night-time talk show on MSNBC, was canned after being caught on camera using a gay slur.

Griffin said his network’s policy is to own up to its mistakes, and said the incidents for which it has apologized don’t “define” the network.

"We quickly took responsibility for them and took action,” Griffin told The Hollywood Reporter. “They were unfortunate, but I'm not going to allow these specific moments of lack of judgment to define us."