Police have charged the operator of a rogue tyre recycling business at the centre of a recent ABC expose with making threatening phone calls to a former associate.

Key points: In July, 7.30 revealed that Tony Di Carlo's Tyremil business was stockpiling tyres at two Brisbane sites

In July, 7.30 revealed that Tony Di Carlo's Tyremil business was stockpiling tyres at two Brisbane sites Di Carlo left threatening voice messages on the phones of two men

Di Carlo left threatening voice messages on the phones of two men The maximum penalty for using a carriage service to make a threat to cause serious harm is 7 years.

Tony Di Carlo has been charged under Commonwealth law with three counts of using a carriage service to make a threat to cause serious harm over a series of voicemail messages he left on the man's mobile phone last week.

In one he allegedly told the man to "go get your gun and bring it", before asking him if he was "ready to meet God".

In July, 7.30 revealed that Di Carlo's Tyremil operation had stockpiled an estimated 800,000 used tyres at two Brisbane sites, despite the concerns of the fire service and the environment department about the risk of a potentially massive fire.

Company insiders told the program that no recycling plant exists at either site and that the company is little more than a dumping ground for used tyres.

Several former workers who spoke to 7.30 said they were owed thousands in unpaid entitlements from two Tyremil companies.

They are unlikely to ever be paid what they are owed because both companies are in liquidation owing creditors more than $1 million.

Threatening calls made during filming of 7.30 story

During filming for the 7.30 story, Di Carlo left voice messages on the phones of a former associate and a former employee accusing them of speaking to the ABC.

He warned one that he would break the man's "f***ing legs" if he made false statements to the ABC.

In an expletive-laden tirade he threatened to "gut" the other.

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Both men made complaints about the calls to the Queensland Police Service, which then launched an investigation.

After the 7.30 story the Queensland Government announced a special waste taskforce would look into Tyremil's operations.

Last week, Di Carlo allegedly left a series of voice messages on the phone of the former business associate.

"I told you not to f*** with me … go get your gun mate, go get your gun and bring it," he said in one of the messages.

"You ready to meet God? Because today I've got nothing to lose c***. I don't give a f*** about cops, anyone … I'm going to make sure we meet our maker today … I'm going to find you today and you're f**ked."

The man reported the messages to police, who charged Di Carlo on Wednesday morning.

He will face court on October 12.

The maximum penalty for using a carriage service to make a threat to cause serious harm is seven years.