The Commerce Commission is investigating The Safety Warehouse's cash drop event to see whether it breached the Fair Trading Act.
Over 1000 people gathered in Auckland's Aotea Square for the event on Saturday after the company announced its $100,000 cash drop event.
Chaos quickly ensued as people fought over discount vouchers made to look like fake money, leading to violence and a number of injuries.
"The investigation will be into whether any representations about the event breached the Fair Trading Act 1986 (FT Act) which prohibits misleading and deceptive conduct," the Commerce Commission said. "The FT Act is one of the Acts enforced by the Commission."
The commission said it's received nine complaints about the event, including two referred by the Police.
Police said on Tuesday that "no evidence of criminal offending" was found after officers reviewed complaints.
"No evidence of criminal offending has been identified from the information received by Police in relation to the money drop," Auckland City Police Inspector Scott Gemmell said.
"Police will be forwarding these complaints to the Commerce Commission for further review."
The Safety Warehouse said on Sunday the event wasn't a prank or scam and people did receive cash.
"The vouchers that were also presented at the event were in addition to the cash that was given away. We never could have expected the inclusion of the vouchers would have created such hostility and a misunderstood narrative," the company said in a statement.
It said the event was based on a live cash draw with live music that was free to enter so anyone could attend.
"After completing our risk assessments it was decided that vouchers should be introduced too. This would assist with mitigating offensive behaviour between patrons. The vouchers consisted of discounts, free goods, house renovation discounts, free accounting services and more."
It added it stands by the marketing and what was issued at the event, saying staff assisted when requested and frequent messages about where to go for first aid were sent out.
Prime Minister Jacinda Ardern condemned the event and called on The Safety Warehouse to apologise.
"I cannot fathom how at any point someone can think that's a good idea. Clearly it was not and it's caused harm," she said on Monday. "They should apologise."