Two people have died and two more remain in a critical condition in hospital after suspected overdoses at the Defqon.1 music festival in Sydney’s west yesterday.

Police said a 23-year-old man and a 21-year-old woman died in Nepean Hospital after collapsing at the Defqon.1 festival in Penrith about 9:00pm.

Emergency services at the event responded to multiple reports of suspected drug overdoses.

A 26-year-old is in Nepean Hospital in a critical condition while a 19-year-old man was airlifted in a critical condition to Sydney’s Westmead Hospital where he remains in intensive care.

Police said 13 more attended Nepean Hospital for treatment for drug-related issues, while up to 700 people sought help from medical staff at the music festival.

Police formed Strike Force Highworth to investigate the deaths and police are appealing for anyone with information to come forward.

Ten people were charged with drug supply offences at the festival, including a 22-year-old man from Bankstown who was charged with supplying a prohibited drug, greater than a commercial quantity, after he was allegedly found with 20 packets of GHB.