Police are warning those planning to go to the Wellington sevens on Friday to be careful about what pretend weapons they are carrying.
Thirty-five thousand fans are expected to pack into the stadium on Friday and Saturday
Most people are going in costume, and that has police advising people to think twice about what they are wearing.
Inspector Simon Perry says costumes will be scrutinised, with anything that looks like a weapon or could be potentially dangerous being confiscated.
He says while no one has any intention of injuring someone with an object like a wooden sword, often people can get carried away and that leads to someone being injured.
Perry says they have no problems with pretend weapons made of foam, like swords, wands or spears, but it is sharp objects that won't be tolerated.
Police are planning a zero-tolerance approach to bad behaviour at the tournament.
Perry says the message for fans is that they should enjoy themselves without spoiling the atmosphere for others.
He says what spoils the event is people getting too intoxicated and then start becoming abusive and offensive. 
Perry says those people will be arrested and evicted from the ground.
Those heading to the event are being told to expect one of the loudest tournaments yet.
General manager Steve Walters says every year they try to introduce new entertainment on and off the field to embellish what is already happening.
He says this year is no exception with a number of surprises in line for ticket holders.
Source: TVNZ