Officers are detaining six people as they look into a significant "virtual vehicle scam.".
Following the execution of warrants in Rotherham, Doncaster, Essex, and Hampshire, four men and two women, according to South Yorkshire Police, were detained.
The arrests were made as part of a campaign against online scammers who advertise discounted car sales only to take the money and disappear with the buyers' purchases.
All six suspects are still being held.
According to the police, four men and one woman, all between the ages of 28 and 33, were detained on suspicion of conspiring to commit fraud, fraud by false representation, and money laundering.
Another woman, 27, was detained on suspicion of neglecting her children.
A police spokesperson claimed that virtual vehicle fraud had targeted "hundreds of victims" throughout the UK.
The arrests were made as part of a "large-scale, multi-agency investigation into the organized crime group who have been committing these frauds across the country for a number of years," according to Det Ch Insp Anna Sedgwick, who oversaw the operation.
"Never, ever transfer money to anyone, no matter how nice or legitimate they seem, without having physically seen the car first," she continued.
"We have seen a significant increase in reports of this scam in recent years, so it's crucial that buyers take extra precautions to verify the seller is legitimate before handing over any money or personal information.
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