Norwich City are appealing for witnesses after a fan set off a flare.
The flare was ignited at the Canaries' FA Cup third round match against Peterborough United.
It was lit during the game at London Road on Saturday January 5.
The club said that the lighting of the flare during the second half in the Norwich City section had potentially endangered supporters in the area and led to 'a number of' complaints.
The club is now appealing for witnesses.
If you can help identify the perpetrator contact the club's head of legal services Jamie Arnall by emailing jamie.arnall@ncfc-canaries.co.uk or by telephoning Norwich City on 01603 760760.
The club said it also wanted to remind supporters that the lighting of flares or any incendiary device at games was illegal and unsafe.
It can also lead to the club being sanctioned by football authorities.
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