Police have busted a Vietnam-based scam ring suspected of stealing more than 10 billion won ($7.5 million) through phishing schemes involving fake mobile wedding invitations and delivery notifications, officials said Friday.

Last week, Korean and Vietnamese authorities apprehended seven individuals, six of whom -- including the leader -- have been extradited to Korea.

The criminal ring is accused of stealing around 10 billion won, the largest amount recorded in such phishing scams, from 230 victims. They did so by sending fake text messages disguised as wedding invitations, funeral announcements, parcel delivery notifications and messages impersonating family members. Once victims clicked the link, malware was installed on their phones, allowing the criminals to extract funds from their bank accounts.

In total, police have arrested 86 individuals, both in Korea and overseas, in connection with the phishing operation.

The investigation was launched in July last year when police in North Gyeongsang Province received a report from a victim who had been scammed after receiving a mobile wedding invitation.

By analyzing over 300,000 transactions across 70 fake accounts used to launder the money, police were able to apprehend two Vietnamese nationals operating in Korea, with one of them now in custody.

Police said they officially began working with Vietnamese authorities last September to share intelligence and prevent further damage.

As the investigation started closing in on the suspects, two members of the ring turned themselves in, while three others were arrested by Vietnamese authorities last month. The ringleader was caught in Ho Chi Minh City on Sept. 4.