England's Euro 2020 qualifier in Bulgaria was suspended twice after visiting players were subjected to racist abuse.
The clash in Sofia was temporarily halted during the first half and the stadium announcer warned home supporters the game could be abandoned if the chanting did not stop.
The announcement said: "Because of racist behaviour which is interfering with the game, the referee has indicated he may have to suspend the match.
"Please be in no doubt that the game may be suspended and abandoned if racist behaviour continues."
But a section of fans continued to aim vile taunts at the England players, including debutant Tyrone Mings and Raheem Sterling.
The officials stopped play again but following consultation with Gareth Southgate and Bulgaria boss Krasimir Balakov, the action resumed.
England currently lead 4-0 at half-time via goals from Marcus Rashford, Sterling and a Ross Barkley double.
UEFA's three-step racism procedure at first sees the referee stop play and request an announcement demanding the racist behaviour stops.
The second step involves the match being halted again and players sent to the dressing room as a second announcement is made over the tannoy.
The third and final step results in the game being abandoned.
