A flare was reportedly thrown by Liverpool fans towards Manchester United supporters at Old Trafford during Wednesday evening's Capital One Cup match.
Footage has emerged of the lit flare being tossed from the East Stand housing Liverpool fans during their side's 1-0 defeat to United in the third round of the competition.
According to the Daily Mail, the Football Association has contacted both Liverpool and the Premier League champions over the incident involving a 2,000-degree flame.
Reports have also claimed that Greater Manchester Police made 10 arrests at the match, but none was related to the flare-throwing incident.