Luke Eliot, The West Australian Updated September 22, 2012, 2:50 am

Police figures show so-called Nigerian scammers have fleeced West Australians of more than $6.5 million since May - or more than $1.5 million a month for the past four months.

The scams, known as advanced fee fraud, have operated worldwide for decades and take a wide variety of forms.

They essentially involve fraudsters convincing victims to send money to get a benefit - which can be financial or, in some cases, relate to personal relationships.

In May, major fraud squad detectives launched Operation Sunbird to investigate the frauds.

They identified about 1200 people who sent money overseas and about 250 of them were regarded as potential victims.

They were identified through big cash transfers they made to "high risk" areas - particularly West African nations Nigeria, Ghana, Benin and Sierra Leone.

Police then wrote to these people warning of their plight. "Two people contacted the major fraud squad in recent months and advised that they were on the verge of suicide had police not intervened," Det-Sen. Sgt Dom Blackshaw said.

Of the 250 people who got warning letters, 13 continued to send money to West Africa.

Last Thursday, _The Weekend West _spoke to a man who sent up to $100,000 to a fraudster he met on an online dating site.

That same day, detectives had a report of a woman who sent most of her life savings to a man she met on another dating site.

"Remember that once you send money to someone it can be very difficult to get it back, especially when they are based overseas," Det-Sen. Sgt Blackshaw said.

A separate police operation called task force Galilee identified 438 WA victims of so-called "boiler room" scams. These fraudsters mass-market scams online through telemarketing or with door-to-door sales. They generally offer big returns on small investments.

Crime statistics published on the WA Police website show a 69 per cent increase in fraud offences in the past financial year, but the rise was attributed to a change in how the offence was recorded.

The figures previously only included offences reported to police but they now include potential frauds, including suspect money transfers.

Police hope the change will give a clearer picture of the impact of the crime, which could in turn help determine where to divert resources.