NEW YORK (CBSNewYork) — Hours after saying Colin Kaepernick wasn’t black and therefore did not understand the discrimination Americans of color face each day, former NFL safety Rodney Harrison issued an apology Tuesday.

In an interview on Houston’s SportsTalk 790 on Tuesday morning, Harrison discussed the 49ers quarterback’s controversial decision to sit down for the national anthem.

“I’m a black man, and Colin Kaepernick, he’s not black,” Harrison said. “He cannot understand what I face and what other young black men and black people or people of color face on a every single (day) basis when you walk in the grocery store, and you might have two or three thousand dollars in your pocket and you go up into a Foot Locker and they’re looking at you like you’re about to steal something. I don’t think he faces those type of things that we face on a daily basis.”

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Kaepernick is biracial — his birth mother is white — and he was adopted by white parents. In a series of posts on Twitter on Tuesday afternoon, Harrison said he did not mean to offend anyone and insisted he did not know Kaepernick was of mixed race.

“I should not have called Colin Kaepernick’s race into question during this morning’s radio interview,” the two-time Super Bowl champ and NBC analyst tweeted. “It was a mistake and I apologize.”

Kaepernick ignited a national controversy after refusing to stand for “The Star-Spangled Banner” on Friday before the 49ers preseason game against the Green Bay Packers. He said he was protesting against “a country that oppresses black people and people of color.”

“To me, this is bigger than football, and it would be selfish on my part to look the other way,” Kaepernick said. “There are bodies in the street and people getting paid leave and getting away with murder.”

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Kaepernick said he will continue to sit for the anthem until there is “significant change.”

Harrison said in the radio interview he believes Kaepernick’s heart is in the right place but questioned his methods.

“If he really wants to make change, maybe what he needs to do is maybe write a check out of that $11 million salary that he’s making and maybe donate it toward a cause or something like that for people that are fighting for injustices against people of color,” Harrison said. “That’s how you make change. And I’m not just saying writing a check, but just sitting against the national anthem, you’re offending a lot of people that sacrificed and died, man, basically for the freedoms that we have right now.”