The Forensic Crash Unit is investigating a serious two-vehicle crash in Logan Central overnight, on January 21.
Initial investigations indicate a red Ford Falcon was travelling north along Bardon Road around 11pm when it crashed with a white Toyota Hi-Ace van travelling in the opposite direction.
A 23-year-old male driver of the sedan and two male passengers, aged 23 and 21, suffered life-threatening injuries.
A 35-year-old female driver of the van, and a 63-year-old male passenger, also suffered life-threatening injuries.
All five people have been transported to hospital for treatment.
Anyone with information or vision of the crash, or the moments leading up to it, are urged to contact police.