POLICE remain in the dark as to what has happened to missing woman Tina Greer.
The girlfriend of a Fink motorcycle gang member disappeared almost a month ago from near Aratula.
Police have expanded their search area to Lake Moogerah, south of Kalbar, using sonar and divers to search for her body.
Mounted police are also being used to search the creeks surrounding the lake.
Ipswich Detective Inspector Lew Strohfeldt said while the case officially remained a missing person investigation, police were searching the lake for a body.
"We're looking to see if we can find any human remains in this lake," he said.
"We can't say whether Tina will be found alive and well, whether she may have had some sort of an accident or if she has been the victim of some sort of foul play, we just don't know."
Divers have been scanning the lake with sonar for the past two days and will continue today.
They are yet to find any objects of interest.
Insp Strohfeldt confirmed Ms Greer's boyfriend was a member of the Finks motorcycle gang.
While police had talked to him, they were not in regular contact and were uncertain of his present location.
"We have spoken to him, but as I said we have got no information that would assist us in locating Tina," Insp Strohfeldt said.
Police divers have been scanning the lake using the same sonar technology used to find shipwrecks.
Information received from the device will be used to identify non-natural objects hidden underwater.
Divers will then investigate any objects of interests they identify.
Ms Greer was last seen on Wednesday, January 18 leaving her home in Beechmont on the Gold Coast hinterland.
Her car, a maroon Holden Commodore was found on Governor's Lookout containing her belongings including phone and handbag.
Police are urging people who may have seen or have any information about Ms Greer or her car to contact Crime Stoppers on 1800 333 000.
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