The only African-American driver in the top US NASCAR racing competition has condemned a "despicable act of racism" in which a noose was left in his garage.
Driver Bubba Wallace, who has recently spoken out in favour of the Black Lives Matter movement, said the incident was a painful reminder of how far the US had to go to combat widespread racism.
"Today’s despicable act of racism and hatred leaves me incredibly saddened and serves as a painful reminder of how much further we have to go as a society and how persistent we must be in the fight against racism," he wrote in a statement posted on Twitter.
"We will not be deterred by the reprehensible actions of those who seek to spread hate."
"As my mother told me today, 'They are just trying to scare you'. This will not break me, I will not give in nor will I back down."
NASCAR has launched an investigation into the incident, which it described as a "heinous act".
"Late this afternoon, NASCAR was made aware that a noose was found in the garage stall of the 43 team," NASCAR said in a statement.
Driver Bubba Wallace next to his racecar, bearing the hashtag 'Black Lives Matter' Source: AP
"We are angry and outraged, and cannot state strongly enough how seriously we take this heinous act.
"We have launched an immediate investigation, and will do everything we can to identify the person(s) responsible and eliminate them from the sport.
"As we have stated unequivocally, there is no place for racism in NASCAR, and this act only strengthens our resolve to make the sport open and welcoming to all."
Mr Wallace has been a vocal activist following the death of George Floyd earlier in June, with his car bearing the 'black lives matter' hashtag on its livery during a race on 10 June.
Earlier this month, NASCAR banned the Confederate flag from all races as the sport moved to distance itself from a checkered past on race.
The decision has proven controversial among some supporters of the sport, which has been traditionally popular in America's south.
During the latest race weekend, protesters flew the confederate flag from their pick-up trucks outside the racetrack.
And before Sunday's race, a plane flew above the track with the confederate flag in tow and a second banner that said "DEFUND NASCAR".
Earlier this year, driver Kyle Larson was fired by his team and given an indefinite suspension from competition, after he used a racial slur during a publicly-streamed virtual race.
