Former Liverpool striker John Aldridge has branded the Manchester United fans who sang vile chants about the Hillsborough and Heysel disasters at yesterday's Youth Cup tie at Anfield as "disgusting".
Three United fans were arrested and six ejected from the ground during the match, which the visitors won 3-2 from 2-0 down with both sides having a pair of players sent off.
"I have never seen anything like that before at a youth game and I never want to see anything like it again. It was disgusting," said Aldridge, who was in the team at Hillsborough when 96 Liverpool fans died in 1989.
"You get used to banter from United fans when they come to Anfield but to hear those songs about Heysel and Hillsborough was just horrible.
"The level of abuse was absolutely sickening.
"There was evidently a group who had just come to cause problems and I felt sorry for the families in the Manchester United end who just wanted to watch a game of football."
The FA Cup semi-final Manchester derby at Wembley 'will cost millions' to police and will be the most expensive security operation ever for a single game in England, according to reports.
The draw has led to calls for Manchester City and United to be played anywhere but Wembley - with some journalists and fans suggesting that the game be moved to Villa Park.
But cup semi-finals have been held at Wembley since 2008 in order to recoup some of the cost of building the national stadium.
Over 80,000 fans will need to be policed - with the majority travelling down from Manchester on the weekend of April 16-17.
If City reach the Europa League quarter-finals, the game is likely to be moved to the Sunday - which would clash with both the London Marathon and a Premier League clash between Arsenal and Liverpool.
The massive operation will involve Scotland Yard, Greater Manchester Police and British Transport Police, who will need to keep supporters apart on trains between Manchester and London.
A Scotland Yard source told the Daily Mail: "From a security point of view, this is a complete nightmare. It will cost millions of pounds."