Two men have faced court charged with torture, kidnapping and other offences while two others are wanted for questioning over a violent attack on a woman in Brisbane.
Detectives say the victim did not know her alleged attackers but there is no threat to the wider community or indication it was gang-related.
Queensland Police say a group of men took the 43-year-old from a home in Doolandella on Friday.
The woman was assaulted, placed in a vehicle and taken to a property at Forest Lake, Queensland Police Acting Inspector Michael Hogan told reporters on Saturday.
He said a firearm was then discharged into the vehicle "at least once" but no one was shot.
A tip-off from a member of the public led officers to an address in Stafford Heights where four men were arrested, with two later released.
Two men, aged 18 and 20, were charged with kidnapping, extortion, torture, armed robbery, dangerous conduct with a weapon, enter a dwelling with intent whilst armed and other offences.
The woman suffered non-life threatening injuries and has since been released from hospital.
"You could obviously understand that she'd been significantly shaken and traumatised by these events," Acting Inspector Hogan said.
Investigators have called on a further two men, ages unknown, to come forward for questioning about their alleged involvement.
"There's no indication it's gang related at this stage, it's certainly something that we do look into as the Investigation progresses," he said.
Crime scenes were established at three properties and a car taken away for forensic examination.
The investigation remains open and anyone with information about what happened or footage from the area has been asked to come forward.