Police have charged a number of people following a dance music festival held at Penrith last night.
The DefQon.1 music festival was held at the Sydney International Rowing Centre between 10:00am and 10:00pm and attracted a crowd of approximately 18,500 people.
Officers from Penrith Local Area Command, the North West Metropolitan Region and the Dog Squad monitored the behaviour of festival goers throughout the day.
The police operation targeted anti-social behaviour, drug and alcohol offences and public safety.
During the operation police conducted 550 person searches while there were also 87 drug detections.
81 people were issued court attendance notices for drug possession with the majority of drugs seized being ecstasy and cocaine.
Six people were arrested and charged with supplying a prohibited drug while one person was charged with assaulting police.
275 people received medical treatment for drug and heat related illnesses with seven of those people taken to Nepean Hospital for further treatment.
Meanwhile 30 people were ejected from the festival for intoxication or anti-social behaviour and five motorists returned positive drug-driving tests.
A number of other offences including goods in custody and licensing breaches were detected with investigations into those matters continuing.