Evening kick-off led to football fan clashes, says report
Holding an East Anglian derby football match on a Thursday night was a "critical" error, a confidential police report has revealed.
An investigation was launched after trouble flared at the match between Ipswich Town and Norwich City in April.
A report, released after a Freedom of Information request by the BBC, found the timing of the Portman Road fixture had contributed to the disorder.
Suffolk Police has apologised for mistakes on the night.
Norwich City complained to the force, claiming the policing operation had been "utterly incompetent".
Fans of both teams clashed before and during the match on 21 April, which kicked off at 19:45 BST.
It was the first evening kick-off for a match between the clubs in 13 years.
Police arrested 19 people and 13 were removed from the ground.
A report by Suffolk Police's professional standards department said: "The critical issue above all else in respect of the cause of the disorder was to move the fixture from its traditional time of midday on a Sunday to an evening kick-off.
"The evening kick-off afforded rival fans the opportunity to consume large quantities of alcohol, an obvious aggravating factor in this case."
Police and both clubs had wanted the Championship game played on Good Friday.
But the report said the date was switched after Ipswich Town said they could not afford the increased costs of bank holiday police overtime.
The investigation recommended all future derby fixtures should kick off at Sunday lunchtime.
Pubs should also have a "dry hour" before kick-off and police officer numbers should be boosted, the report said.
In its complaint, Norwich City described the policing outside Portman Road as "utterly incompetent" and "grossly negligent".
Supt John Everett of Suffolk Police said the policing operation had been challenging but successful.
"We didn't have any significant disorder. We had a very, very small number of minor injuries and no significant damage to pubs, which we've seen in the past with these derby games.
"Of course, we're more than happy to learn and to react positively to constructive criticism."
A spokesman for Ipswich Town said the report contained "significant inaccuracies".
"These discrepancies include the decision-making process to play the game on the Thursday," he said.
"A meeting with all parties is already planned for February when we will be seeking to iron out these inaccuracies. Until that time, the club will be making no further comment on this issue."