Police have arrested seven people, discovered a drug lab and believe a car fire overnight is linked to their investigation into a fatal shooting in Brisbane's south-west earlier this week.
A 38-year-old man was shot in the chest at close range outside a house in Oxley on Tuesday, with the alleged attack involving a group of people armed with multiple firearms.
Two "priority persons of interest" arrested yesterday led to a breakthrough in the investigation.
A 26-year-old woman was found in the CBD on Tuesday afternoon and taken into custody on unrelated charges.
A 26-year-old man was arrested on unrelated charges at a Mackenzie address about 11pm on Wednesday after a major operation involving specialist police and detectives.
Police Superintendent Andrew Massingham said five others were then arrested at the house, where a methamphetamine lab was found.
"Another three males and two females were also located at that address and upon entry by specialist officers we've located an operational clandestine drug laboratory," he said.
Just after 11pm an Audi A3 sedan, previously identified as a vehicle of interest, was involved in a fire at an address on Gladstone Road in Dutton Park that destroyed six other vehicles.
Superintendent Massingham said he was confident there would be developments in the homicide investigation today.
"I consider this a major step forward in the investigation," he said.
"I certainly indicate that my two priority persons of interest are with us, I'm confident that any others that were present on that night we'll be able to work through and get resolution of that today or tomorrow."