A missing Brisbane mother may have tragically died after getting into an industrial bin before its contents were picked up by a rubbish truck, investigators believe.

Natarn Auld, 38, left her Capalaba unit in December but hasn't been seen or touched her phone, bank account or social media since.

Natarn Auld.
Natarn Auld.

In a tragic set of circumstances an intensive investigation by police has now confirmed the mother's phone tracked from Capalaba to the Northgate area in Brisbane's north at exactly the same time as a rubbish truck in the early morning.

The last confirmed sighting of the mother-of-three was CCTV footage at 3.30am on December 14 on Redland Bay Rd at Capalaba after she left her home at Mount Cotton Rd on foot, 1-2km away.

Ms Auld is seen in footage walking alone. Her phone then remained in the location until about 4.10am before tracking to the city's north.

Detectives say there is nothing to suggest the mother-of-three was separated from her phone and she had been known to occasionally look for items in charity bins.

A thorough investigation found the mother was not seen in any areas - or on CCTV - in any other directions away from the bin.

Capalaba mum Natarn Auld was reported missing in December.
Capalaba mum Natarn Auld was reported missing in December.

Investigators have not found the mother or her phone and it's unclear how extensive a search would be required to retrieve them.

News Corp understands one possibility being examined by police is that the mother may have fallen asleep before being picked up by the truck, given the time of day she was there.

The night before her disappearance, on December 13, Ms Auld was captured on CCTV going to a BP service station on Redland Bay Rd at Capalaba and bought food about 11.40pm.

She was with a man, a friend, at the time and was wearing long grey pants, a jumper, thongs and a gold necklace.

Police have said they are not treating him as a person of interest.

Police are preparing a report for the coroner.

Originally published as Grisly industrial bin theory in search for missing Brisbane mum

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