Police previously said the four who died after attending the event at Sunway Lagoon on Dec 31 were suspected to have taken ecstasy.

Their deaths had prompted authorities to suspend concert permits in Selangor, with the state government saying it would review concert guidelines.

Subang Jaya police chief Wan Azlan Wan Mamat today said the toxicology reports, which the police received from the chemistry department last week, would be referred to University Malaya Medical Centre.

However, he said police could not reveal the type of drugs traced in the victims’ blood as the full reports from UMCC, including the autopsy reports, are still pending.

In a statement today, Wan Azlan also said police have recorded statements from 52 people, including the deceased’s friends, and event staff.

“Police have yet to record a statement from the 30-year-old man who is still receiving treatment at UMCC as he is not in stable condition yet,” he said.

“We will do so once we get approval from the hospital.”

Before this, another individual had been discharged from the hospital.

On Jan 2, Selangor police chief Hussein Omar Khan said the four who died were among seven people admitted to Kuala Lumpur Hospital and UMCC after showing similar symptoms.

He said the seven did not attend the concert together but were present separately with friends and family members. Two of the patients were still being treated and one had been discharged.