"I'd seen this by the mall and that sort of place but never in the children's playground."
Murrie posted the video to his Facebook account on August 31, shortly after it was filmed.
The two people were sitting in the playground, visibly high on synthetic cannabis, when the man approached them.
They appeared lethargic, moving slowly, and walked away as Murrie spoke to them.
"Youse need to get out of here bro .. youse are in a children's playground," he tells the pair.
"Look at you two you're a mess."
He says he watched them go into a nearby house.
Murrie says he "acted on instinct" and was "emotional and angry" as he spotted the two drug users.
"I know a few people who are now beggars [because of the drug]," he said.
"It's a really hard one to approach and I don't know what the answer is," he said, adding that, regardless of the solution, he cannot keep seeing drug use in children's playgrounds.
"What I think police and government need to do is make synthetics an A class drug, punish the users and dealers with A class penalties and also start synthetics rehabs across the country before it gets worse," he added.
The family of the woman in the playground hadn't seen her in about a month when they spotted her in the online video. Her brother spoke to the NZ Herald about her struggle with addiction and how they just want her home.
Police did not attend the incident and a spokesperson said "no report has been made to police".
"Police would encourage anyone who finds themselves in a situation where they believe a person may need medical attention to call an ambulance immediately," they added.