Serena Williams vows she "won’t be silent" about police violence in the U.S.

Serena Williams has become the latest high-profile athlete to speak out about police violence in the United States.

The No. 2 ranked player wrote a lengthy post on her Facebook page on Tuesday, sharing a recent experience of riding in her car with her 18-year-old nephew, and feeling anxious as they approached a nearby police car.

“In the distance I saw cop on the side of the road. I quickly checked to see if he (her nephew) was obliging by the speed limit. Than I remembered that horrible video of the woman in the car when a cop shot her boyfriend. All of this went through my mind in a matter of seconds. I even regretted not driving myself. I would never forgive myself if something happened to my nephew. He's so innocent. So were all ‘the others,’” she wrote.

The 22-time Grand Slam winner Williams has encountered racism during her career, most notably during an incident back in 2001 at Indian Wells when during Serena’s final, her sister Venus and father Richard were booed and reportedly had racial slurs and threats directed at them by a hostile crowd. The Williams sisters boycotted the event for 14 years, with Serena only making a return to the tournament last year. Venus ended her boycott earlier this year.

With her latest post, Williams joins a chorus of other high-profile athletes such as NBA stars LeBron James and Steph Curry who have spoken out about police brutality and come out in support of San Francisco 49ers quarterback Colin Kaepernick, who has been taking a knee during the U.S. national anthem ahead of games in protest of the mistreatment of minorities, including African Americans, in the U.S.

In her Facebook post, Williams wrote that she believes "not 'everyone' is bad.”

“It is just the ones that are ignorant, afraid, uneducated, and insensitive that is affecting millions and millions of lives. Why did I have to think about this in 2016? Have we not gone through enough, opened so many doors, impacted billions of lives? But I realized we must stride on — for it's not how far we have come but how much further still we have to go,” she wrote.

"I then wondered then have I spoken up? I had to take a look at me. What about my nephews? What if I have a son and what about my daughters?

"As Dr. Martin Luther King said, 'There comes a time when silence is betrayal.'"

She ended the post by writing “I Won’t Be Silent.”