Most of the National Football League's Houston Texans team knelt in protest as the national anthem was played for Sunday's game in Seattle, an apparent rebuke of team owner Bob McNair for his remark about "inmates running the prison."

Backlash over the comment rekindled a national debate over NFL players, mostly African-Americans, who have broken with tradition by taking a knee or raising their fists during "The "Star-Spangled Banner" to protest racial bias in the U.S. criminal justice system.

U.S President Donald Trump escalated the controversy in September when he suggested owners should fire any "son of a bitch" who refused to stand for the anthem.