Anthem singer at NBA game kneels during performance

  (Photo Cred: Jasen Vinlove/USA TODAY Sports)

Denasia Lawrence kneels while singing the national anthem before the Heat-76ers preseason game on Friday night, revealing a shirt with the phrase "Black Lives Matter."

Lawrence, called the Black Lives Matter movement a "rallying cry" while explaining her decision to kneel in a Facebook post early Saturday.

"We're being unjustly killed and overly criminalized," Lawrence wrote. "I took the opportunity to sing and kneel to show that we belong in this country and that we have the right to respectfully protest injustices against us."