Four people have been arrested in the UK following an investigation into scams involving calls from fraudsters pretending to be IT support staff.
It follows two years of work by City of London Police and Microsoft, who teamed up to tackle the problem.
The perpetrators commonly pretend to be phoning on behalf of the US company.
The inquiry indicated that many of the calls originated in India but two men and two women in England have been accused of involvement.
They include a 29-year-old man and a 31-year-old woman from Woking in Surrey, who were arrested on suspicion of fraud. Both have been bailed.
A 37-year-old man and a 35-year-old woman were arrested in South Shields, Tyneside, on suspicion of fraud. Both were released pending further inquiries.