The “queen pin” of a Sydney drug syndicate has been charged with murder after allegedly ordering the killing of a drug cook and his girlfriend in 2013.

Dung Thi Ngo, 41, was arrested at Silverwater Women’s Correctional Centre on Thursday and charged over the deaths of Son Thanh Nguyen, 39, and his girlfriend Thi Kim Lien Do, 35.

Earlier this week, police arrested a man they believed carried out the killings.

Kevin Ly, 25, fronted court on Tuesday accused of beating and strangling Mr Nguyen and Ms Do on the woman’s orders, before wrapping their bodies in sheets and dumping them in separate locations.