A 12-month investigation culminated in three arrests, with the Australian Federal Police on Wednesday announcing they charged a trio for allegedly dealing with at least $1 million worth of crime proceeds.

The trio included the alleged ringleader of the syndicate, a 49-year-old woman from Springvale South in Melbourne’s southeast, along with a 63-year-old man and a 61-year-old woman from Noble Park, also in the southeast.

They are due to appear on Thursday in Melbourne Magistrates Court, where the maximum penalty for the offence is 20 years in prison.

Police say the alleged syndicate members helped launder millions in cash through a licensed gaming venue at Springvale by buying jackpots from patrons.

They allegedly paid the winners cash if they handed over their winning cheques, which would then be issued in a syndicate member’s name, and later attributed as legitimate gambling winnings in the bank.

The 12-month investigation, known as operation Avarus Arvon, was prompted by a tip off from the Australian Transaction Reports and Analysis Centre (AUSTRAC).

The Victorian Gambling and Casino Control Commission and National Australia Bank also assisted in the operation.

AFP acting assistant commissioner Raegan Stewart said AFP partner agencies flagged suspicious activity after noticing a high number of cheques being issued from the same family.

The commission later discovered the Greyhounds Entertainment pokies venue in Springvale allegedly issued an abnormal amount of cheques compared to other venues, between November 2021 and June 2022.

Nearly 75 per cent of the cheques, valued at more than $4.7 million, were issued to a select group of people, all suspected to be linked to money laundering.

AFP investigators on Tuesday executed search warrants on a commercial property in Springvale, a home in Noble Park, and a home in Springvale South.

They found more than $170,000 in cash and gold bullions inside the Springvale South home, and money was allegedly discovered hidden inside plywood in a bedroom.

Ms Stewart said police were still investigating the syndicate size and further arrests were likely.

“We seek to cripple their business models. The AFP has investigators, analysts and lawyers working consistently to outsmart anyone who accumulates wealth they cannot explain or lifestyle they cannot lawfully justify,” she said.

The gambling and casino control commission is continuing investigations into the Springvale venue and its staff over any potential breaches of Victorian gambling laws.

Victorian Gambling and Casino Control Commission chief executive Annette Kimmitt said the Springvale venue and the entire gambling industry had been put on notice.

“Investigations into the venue and its staff are ongoing,” Ms Kimmitt said.

“And if we find any breaches of Victoria’s gambling laws, we will take action and that could extend to some pretty hefty fines and to even cancelling the operator’s license.”