Aston Villa prevailed 2-0 in an FA Cup quarter-final against Midlands rivals West Brom, but their win was marred by thousands of fans entering the field of play.
After Fabian Delph had opened the scoring, Scott Sinclair secured victory for Villa five minutes from time, and dozens of supporters came on to the field to celebrate.
There was another invasion during stoppage-time, and when the final whistle was blown, thousands of fans ran on to the pitch.
When contacted by Perform, an FA spokesman confirmed the governing body would begin an investigation into the incidents on Monday.
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