Australia's police has confiscated $6.4 million in cryptocurrency as part of a global crackdown on Ghost, an encrypted communications network, authorities allege was “built solely for the criminal underworld,” a statement said.

The seizure of the cryptocurrency comes two weeks after the AFP arrested a Sydney resident Jay Je Yoon Jung, 32, the alleged mastermind behind Ghost. He appeared in a Sydney court on Wednesday to face the charges. Another man who allegedly distributed the app has also been arrested.

The seized crypto has been transferred into secure AFP cryptocurrency storage and the authorities will seek its permanent forfeiture.

The effort is titled Operation Kraken but Kraken the cryptocurrency exchange "has not been the subject of any Operation Kraken investigations," an AFP spokesperson wrote in an email to CoinDesk. "Operation Kraken was an investigation into a dedicated encrypted communications platform."

A Kraken spokesperson said, “We’re disappointed by this operation’s codename, which has absolutely nothing to do with our brand."

The crackdown last month saw 700 AFP members execute 93 search warrants, arresting 46 people, intervening in 50 threats to life, and seizing 30 illicit weapons and 200 kg of illicit drugs, the AFP said.

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