A total of 29 people were sent to hospital in Edmonton during during a weekend-long rave billed as Canada’s largest electronic music festival.
Two people are in critical condition and another four remain in serious condition in hospital.
"In my three years of doing this job, I have never seen an event with these sorts of numbers," said Sgt. Nicole Chapdelaine.
"Some people have suggested that there’s no difference between this event ... and a busy Saturday evening on Whyte Avenue," she said. "I am here to tell you there is absolutely no comparison."
City councillor Kerry Diotte attended the Elements Music Festival Friday night, when four of the 29 people were taken to hospital.
"I've seen worse situations on Whyte Avenue to be honest," he said. "I was quite struck by the fact people were fairly nice."
"It didn't seem like anybody was looking for trouble," he said. "If they did, they'd have been thrown out of there. There was very little tolerance for that."
Police used drug-sniffing dogs which helped in charging several individuals with drug-related offences, said Chapdelaine.
Most of the patients were sent to hospital after ingesting too much ecstasy or alcohol, said health officials.
Many, including festival-goer Samantha Vickery, were impressed with the security at the event, which was expected to attract more than 10,000 people over two nights.
"Everyone was just having a good time," she said. "Everyone was just a happy, mangled mess."
Prior to the event, police and city officials expressed concern how a spike in sexual assault complaints and drug overdoses during raves puts pressure on emergency services.
The weekend's event did not allay any of those concerns, said Chapdelaine.
"It speaks volumes that Alberta Health Services had assigned a doctor, a mobile triage unit and EMS crews on-site for this event," she said. "They were definitely required."
Dale Weiss with Alberta Health Services said advance planning and having a doctor at the site really paid off.
"I know that on at least one occasion, there was a very critical patient that was seen, assessed by physicians, and physicians actually came with the ambulance to the hospital and arranged their care immediately," Weiss said.
Karen Smith, executive director of the Sexual Assault Centre, said she was pleasantly surprised by the lower number of calls it received on the weekend.
"On a typical weekend, we would have 20 calls, and after the last rave we have double that," she said. "This weekend, we had 14 calls."
Rave promoters claimed they are being unfairly targeted and events like the Elements Music Festival put Edmonton on the map — artistically and musically — by bringing a world-class event to the city.