After the extremely violent final match of the first Quidditch World Cup in 1473, seven hundred fouls were identified and listed. Most of these violent fouls were the result of players using wands to curse opposing players, which led in 1538 to an outright ban on using a wand against the opposing team (QA6).
The official rules, set down by the Department of Magical Games and Sports in 1750, include this statement:
Wands may be taken on to the pitch’ but must under no circumstances whatsoever be used against opposing team members, any opposing team member’s broom, the referee, any of the balls, or any member of the crowd (QA6).
Members of the crowd, however, don’t tend to follow such rules, sometimes resulting in chaos, as happened in an infamous Puddlemere United and Holyhead Harpies contest (DP4).
An attempt to ban wands being brought into Quidditch stadiums by spectators at the 1974 Quidditch World Cup was the cause of the incident known as "Royston Idlewind and the Dissimulators" - where wizards were able to outwit the Ministry officials who had organised the tournament (QWC).
Lexicon timeline of Quidditch
Lexicon list of Quidditch fouls
Although the date printed on the fourth Daily Prophet Newsletter (DP4) is 1 October 1999, the timeframe for this event is 1992-1993.
From the Web
Harry Potter Wiki: Wand Ban
Screenshots of the Daily Prophet coverage of the 2014 Quidditch World Cup (originally from Pottermore), written by J.K. Rowling, and saved on Imgur:
WizardingWorld (Pottermore) features:
Tags: competitions/competitors fairness match Quidditch history rules violent Quidditch fans violent Quidditch match wands Wizarding laws