More than 600 people were under investigation for posing as I.R.S. officers and sending text messages to American cellphone numbers demanding money.
By HARI KUMAR
NEW DELHI - The call centers outside Mumbai looked like many others that have sprung up across India in recent decades. But investigators say the hundreds of people who worked at the nine centers had an unusual assignment: posing as Internal Revenue Service officers and demanding money from American taxpayers.
The operation had been in place for a year before an informer went to the authorities a few weeks ago. An investigation led to raids, with officers blocking exits on each floor of a building that housed seven of the centers, the police said on Wednesday, adding that 70 people were arrested and 600 people were under investigation.