A football fan whose tongue-in-cheek appeal for beer money went viral and raised more than $1 million for a children's hospital apologized Tuesday for offensive tweets he posted seven years ago.

The old posts by Iowa State University football fanatic Carson King, which were uncovered by a local journalist and reported on in a story published Tuesday night, led to Anheuser-Busch Cos. announcing it would end its partnership with King.

Then in a twist, it came to light that the journalist himself apparently had posted offensive tweets in the past, including some that appeared to mock gay marriage, according to The Washington Post.

King's rise to sudden fame came innocently enough when he showed up early for the annual University of Iowa vs. Iowa State football game Sept. 14.

He held a homemade sign proclaiming, "Busch Light supply needs replenished," and giving his Venmo address for donations. That caught the attention of ESPN's "College GameDay" cameras.

When buckets of beer money began to pour in, King, 24, decided to donate the funds, minus the cost of one case of Busch, to the University of Iowa Stead Family Children's Hospital.

Anheuser-Busch and Venmo got into the act and also pledged money to the hospital, which has raised more than $1.1 million in the viral fundraiser.

The feel-good story prompted editors of the Des Moines Register to send reporter Aaron Calvin to meet King for a profile. And during the journalist's routine research, Calvin stumbled on 2012 tweets when King, then 16, seemed to mock black women and the Holocaust.

The reporter approached King with the tweets and he admitted posting them. Before the Register published its story, King called a press conference Tuesday to apologize.

"I am so embarrassed and stunned to reflect on what I thought was funny when I was 16 years old. I want to sincerely apologize," King said. "Thankfully, high school kids grow up and hopefully become responsible and caring adults."

The football fan even lauded the Register, saying the state's largest newspaper "has been nothing but kind in all of their coverage, and I appreciate the reporter pointing out the post to me."

The newspaper published a lengthy statement Tuesday night explaining how it struggled with the question of whether to report on King's old tweets. Its profile of King ultimately mentioned the tweets only at the bottom of the article.

As the story of King's old tweets became news, some social media users did their own background check of Calvin and found offensive tweets on his account, including some that appeared to mock the legalization of same-sex marriage, The Washington Post reported.

Calvin made his Twitter account private, but before doing so wrote early Wednesday that he regretted the old posts.

“Hey just wanted to say that I have deleted previous tweets that have been inappropriate or insensitive,” he wrote on Twitter, according to the Post. “I apologize for not holding myself to the same high standards as the Register holds others.”

The newspaper tweeted at 1 a.m. ET on Wednesday: "The Register is aware of reports of inappropriate social media posts by one of our staffers, and an investigation has begun."

The Register did not name the staffer.

NBC News reached out to the Register and its corporate owner, Gannett Co., for comment but did not immediately hear back.