Tottenham Hotspur and Millwall have confirmed that they will assist the Football Association's investigation into allegations of racist chanting during Sunday's FA Cup quarter-final between the two sides.

A section of Millwall supporters were heard chanting "DVD" and "You're selling three for a fiver" at Tottenham's Son Heung-min - an apparent reference to the racial stereotype of traders selling bootleg copies of films.

The FA is understood to have begun an investigation into the incident and will seek evidence from referee Martin Atkinson's match report in addition to reviewing video footage from the game.

"We strongly condemn the use of any racist language. We shall be passing on all of our footage to the relevant authorities which can assist with the identification of anyone responsible for such chanting at yesterday's game," read a statement from Spurs.

A Millwall statement read: "Millwall have led the way on anti-discrimination initiatives and will continue to do so. The club is assisting the FA with their investigation and will make no further comment until that process is complete."

Son went on to score a hat-trick at White Hart Lane as Spurs stormed to a 6-0 victory over their London rivals.