A 25-year-old woman Sylvia Choi from Oyster Bay has reportedly died at the Stereosonic Music Festival in Sydney from a drug overdose. She suffered a cardiac arrest and was rushed to the Concord hospital but was pronounced dead.

Another woman is in induced coma and around 120 festival-goers have been treated for over-consuming drugs at the do. NSW Police have issued a warning that visitors are "playing Russian roulette" with their lives and that they need to take control of their lives. The festival attracted close to 50,000 revellers.

“This number is alarming and disappointing, especially after we warned revellers about the dangers of drug use,” said Assistant Commissioner Frank Mennilli, reports The Sydney Morning Herald.

According to 9 News, Choi, a qualified pharmacist, consumed a mixture of ecstasy, alcohol and possibly MDMA and fell ill on Saturday afternoon. She was pronounced dead between 9 p.m. and 9.30 p.m. by doctors who tried desperately to revive her.

Mennilli hoped that the post-mortem would help in getting conclusive evidence on the kinds of substances the woman took. The post-mortem will be done on either Sunday afternoon or Monday.

The second woman, 22 years of age and probably from UK, was taken to Westmead Hospital after she was found unconscious. She was placed into an induced coma. However, her condition has improved and she seems to be recovering fast.

Organisers of the festival told News.com.au that two people had planted drugs before the fences went up. The event was expected to be visited by 150,000 people.

“We were disappointed to learn that two individuals have been arrested allegedly planting drugs at the site and vicinity before the security fences are erected,” said John Curtin of Totem Onelove Group.

Mennilli said that the police’s efforts of warning people of drug use have fallen on deaf ears and this needs to change. The event was expected to be safe and secure after officers from South West Metropolitan Region, Police Transport Command, Traffic and Highway Patrol, Public Order and Riot Squad, Mounted Unit and the Dog Unit undertook a massive police operation.

More than 120 people were treated from the effects of drugs and 69 were charged for possession and supply of drugs while 23 were cautioned for using cannabis and a further nine were taken to the hospital for drug overdose and later discharged. Revellers were in possession of cocaine, LSD and other restricted substances, reports Sydney Morning Herald.

The death of the 25-year-old woman comes two months after 26-year-old Nigel Pauljevic from Albury died at Penrith’s DEFQON1 music festival.

Georgina Bartter, a 19-year-old girl also died last November after consuming ecstasy supplied by her best friend at the Harbourlife Festival.

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