Fans ran onto the pitch after the final whistle and police then fired tear gas leading to the stampede.
Haaland's treble, remarkably his third in successive home Premier League games, took his tally since joining the champions in the summer to 17 in just 11 appearances in all competitions. Foden also had a huge hand in a rampant City display which evoked memories of their famous 6-1 derby demolition of United at Old Trafford in 2011. Foden began the rout after just eight minutes and United were a distinct second best thereafter, although Antony pulled one back and Anthony Martial also claimed two consolation efforts.
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