Two armed men allegedly held up an R18 store and stole synthetic drugs - just minutes before the products were deemed officially illegal.
Police say two men - aged 30 and 18 - were carrying knives when they entered the Stanmore Road store in the Linwood area of Christchurch around 11.20 last night.
An emergency law change made it illegal to buy, sell or possess the products from 12.01am.
They allegedly punched the store owner and made off with a quantity of cash and synthetic drugs. The shop owner's injuries were not serious.
Police were called and a vehicle was stopped nearby. The two occupants of the vehicle were arrested. A third offender is still being sought by police.
A 30-year old man and an 18-year old man, both from Christchurch, will appear in court this morning on charges of aggravated robbery.
Police inquiries are continuing and they're appealing to anyone with information on the incident to phone them on 03 363 7400. Information can also be provided anonymously to Crimestoppers on 0800 555 111.