Millwall fans taunted Leicester supporters after the FA Cup win
The home fans, whose side beat the Premier League champions 1-0, charged towards the away end moments after full-time.
Reporter Oliver Holt tweeted: "Worrying scenes at the Den. Pitch invasion has resulted in Millwall fans massing in front of away end. Few missiles being thrown."
A massive police presence soon followed.
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Full-time celebrations at Millwall and a pitch invasion. pic.twitter.com/2ar2ElhH1l
— Richard Cawley (@RichCawleySLP) February 18, 2017