Reuters

Australian police found $6.5 million worth of gems, jewelry, cash, silver bullion and antiques, in a storage unit on Wednesday. They believe the stash is the result of a string of robberies across Sydney and Melbourne in September.

Police on Wednesday uncovered a treasure trove of allegedly stolen goods in a storage unit in Sydney, Australia, including silver bullion, jewelry and 4 million Australian dollars in cash, according to reports.

The Australian Associated Press reported that the total value of the goods is around $6.5 million, and that the loot is believed to be the result of a string of robberies across Sydney and Melbourne in September.

In addition to the cash and 264 pounds of silver bricks likely cast from melted-down jewelry, New South Wales police found pistols, war medals and precious gems.

Reuters

Included in the treasure trove was 264 pounds of silver bricks likely cast from melted-down jewelry.

They found the items after carrying out a search warrant on a storage facility in Waterloo, Sydney.

Police investigating the September burglaries arrested two men on December 19. The father-and-son pair, aged 56 and 33, are being held in Victoria, The Sydney Morning Herald reported.

Reuters

New South Wales police found 4 million Australian dollars in cash in the Sydney storage unit.

"We believe there may be a number of owners of both commercial and residential premises who are unaware that their safes have been tampered with and entered and that their property has been taken," Acting Assistant Commissioner Mal Lanyon said according to the Herald.

Lanyon said the thieves were highly sophisticated and planned out their robberies carefully, but he did not detail their methodology.

Reuters

In addition to the jewelry and cash, police found pistols and war medals.

Police were urging people to check their safes in case they had been targeted and were unaware of it, the Herald reported.

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Msnbc.com editor Marian Smith contributed to this report.