Leeds are investigating alleged racial abuse by travelling supporters during the defeat to QPR at Loftus Road on Tuesday night.
A couple of videos have emerged on social media of Leeds fans appearing to hurl derogatory racial slurs at the home crowd.
One fan is accused of shouting ‘smelly p***’ and ‘smelly n*****’ at Rangers supporters.
In a statement on their official website, Leeds said: “The club is aware of a video circulating on social media from our Sky Bet Championship fixture against QPR on Tuesday evening.
“An investigation is now underway to identify those involved.
“Racism will absolutely not be tolerated by Leeds United and anyone found to be racially abusive will be banned from attending all games indefinitely.”
Meanwhile, the Leeds United Supporters’ Trust insists the incident does not reflect the Elland Road fan base.
The group tweeted: “We’re disappointed to see allegations of racism by a Leeds fan at the QPR game, there is no place for racism on or off the field.
“This is not a representation of our support base and we will ensure the club are made aware.”
It is the latest in a string of incidents which have shamed English football this season.
Manchester City’s Raheem Sterling suffered alleged racial abuse at Stamford Bridge in December, while a Tottenham fan was banned for life after throwing a banana skin at Pierre-Emerick Aubameyang during the north London derby.
And earlier this month, the FA charged Millwall for racist chants aimed at Everton fans.