A teenage boy remains in hospital after being shot in the chest late on Tuesday night.
Police said the 17-year-old, suffering from a gunshot wound, was dropped at Logan hospital in the early hours of Wednesday morning by people who were believed to be associates and family members.
"He was left at the hospital with a relative," Detective Acting Senior Sergeant Brendan Blyth said.
The boy was transferred to the Princess Alexandra Hospital in Brisbane, where he is in a critical but stable condition.
Investigations led detectives to declare a crime scene at a residence on Mark Lane in Waterford West, where they believe the shooting may have occurred.
A vehicle of interest was located by police on Thursday at Princess Street in Marsden.
Detective Acting Senior Sergeant Blyth said it was believed the boy was with a group of other teenagers in Logan when he was shot by someone he knew.
"We do believe the gunshot wound was inflicted by another person, but we still are investigating a number of leads," he said.
"We're investigating within the Logan district, but we don't have a specific location.
"I don't believe this is a random incident. I believe the associations involved in this particular investigation are known to each other."
Police have not yet been able to speak with the injured teenager.
Detective Acting Senior Sergeant Blyth said there was no ongoing threat to the public.
Police are asking witnesses or anyone with information about the incident to contact them.
