Teens on sex assault charges in Sydney

Three teenagers will face court after allegedly sexually assaulting an 18-year-old woman at a party in Sydney's west.

Police say the woman attended the party at Prospect on Saturday evening with two friends and was sexually assaulted in a bedroom by the three young men, one aged 17 and the others aged 18.

Concerned friends contacted police who made inquiries and arrested the trio, charging them with aggravated sexual assault and refusing them bail.

On Monday the two 18-year-olds will appear at Parramatta Local Court and the 17-year-old will appear at a children's court.