A young man died and three others are fighting for their lives after collapsing at an electronic music festival in West Kowloon cultural hub, where illegal drugs were found.
Chow Wai-ho, a 27-year-old headhunter, was allegedly given a bottle of liquid at the popular Road to Ultra festival on Saturday at the WKCD Nursery Park before falling ill and dying at Queen Elizabeth Hospital an hour later.
Three other festival-goers - two men and a woman -are in critical condition.
The four did not know each other and collapsed at different times during the festival, which ran from noon to 10pm.
A small amount of psychotropic substances was seized in the park after the incident, while drug testings are still ongoing as Yau Tsim District Regional Crime Unit investigates.
A psychiatrist warned that taking narcotics in a heated outdoor environment like the festival while drinking and dancing was "deadly enough to kill even an elephant."
The organizer said on Facebook that it held a "zero-tolerant" attitude towards use of drugs.
In a statement, West Kowloon Cultural District - whose chief executive is Duncan Pescod and board chairman is Chief Secretary Matthew Cheung Kin-chung - sent their condolences to Chow's family and promised to cooperate with the police.
"We regret that four members of the audience were sent to hospital due to heat stroke," the statement said, without any mention of drug abuse.
At about 3.35pm on Saturday, Tai Hoi-ching, 21, was the first to fall unconscious at the venue and the organizers called the police.
Chow blacked out at 9.07pm, followed by Lo Man-sui, 22, at 9.33pm and Lai Siu-hung, 29, at 11.41pm during a post-festival party.
Chow was pronounced dead at QEH at 10.06pm on Saturday. Tai and Lai are on breathing machines in intensive care.
A postmortem examination will be carried out to determine Chow's cause of death.
RTHK quoted a female friend saying someone handed Chow a "clear liquid" before he experienced chills and involuntary shaking. The woman said she saw paramedics trying to help him vomit before he was sent to hospital.
Investigators seized a small amount of illegal substances at the festival venue, including midazolam, which is used as an anesthesia, the rave party drug ecstasy and other drugs.
However, it is understood that all four victims had shown signs of heat stroke, whose symptoms can be similar to a drug overdose.
Police officers visited the hospital at about 3pm yesterday but were unable to take statements from the three critically ill patients.
Family and friends who visited Lai in hospital, said the young film editor was not a drug user or regular drinker.
Psychiatrist Jackie Fu Chi-kin said: "Drug overdose can result in higher heart rate. It overloads the circulation and respiratory system." Should a person abuse drugs in an outdoor environment in hot weather, his or her system overload would be made worse by heat stroke symptoms.
Tickets for the show, which cost from HK$680 to HK$1,980, were sold out.
Though there were security checks at the entrance, some festival-goers said it was so lax that it would have been very easy to sneak in drugs.
Participants said there were only about two to three security guards to manage a crowd of about 1,000 and there were no sniffer dogs.
The WKCDA denied allegations of "lax security" saying in its statement: "[The festival] have engaged around 100 security guards." It said three first- aid booths were set up and free water refills were available. But it is reviewing venture-hire procedures to ensure safety in future.
It was the second year the annual Road to Ultra show was hosted in Hong Kong. It will continue its tour in Tokyo, Rio de Janeiro, Cape Town, Johannesburg, Miami and Seoul.
There were 3,994 reported drug abusers in Hong Kong in the first half of 2017, down 23 percent over the same period last year.
Action Committee Against Narcotics chairman Ben Cheung Kin- leung said: "The committee has been keeping an eye on the changing drug trend."
It will take action including sending social workers to concerts or large-scale festivals.
"Drug abuse is a deadly game," Cheung warned.