FOOTBALL fans have been warned about a massive on-line black market for FA Cup semi-final tickets.

Sunderland will take on Millwall at Old Trafford, Manchester, on Sunday but, despite the fact tickets are only just being issued to season ticket holders and club members, several websites are advertising availability of seats at either end of the ground.

The Football Association (FA) has urged fans to avoid booking via online touts as it risks breaching strict segregation and they could be left paying vastly-inflated figures.

A spokesman said: "It is also not unheard of for unofficial sites to offer tickets and then not fulfil their promises."

A Sunderland AFC spokeswoman said: "While we understand demand is high, we strongly advise supporters not to purchase tickets from any unofficial agency."

About 31,000 Sunderland supporters are expected to cross the Pennines for the match and Greater Manchester Police say officers may intercept coaches to direct drivers to use alternative routes to relieve congestion.

Fans travelling by train are advised to book early on TransPennine services.