. >> reporter: the calls to cindy gervais of new orleans started long after she and her husband already paid off an online loan. but she was told, falsely, she still owed more. >> and that i was a no-good deadbeat and that -- i would have the worst -- i would spend the night in jail and my family wouldn't be able to get me out. >> reporter: though she sent them more than $1,800 to pay off a debt she did not owe. and the chairman of the federal trade commission says sin di s not alone. >> we know these folks have collected at least $5 million from american consumers, that they made at least 2.5 million phone calls to 600,000 different numbers. >> reporter: authorities say the scammers are so believable, because they often have the victim's actual financial information. >> let me reveal the last four digits of your social. it's 9-2-8-1. >> reporter: it's information scammers buy from dishonest online loan brokers. >> that information is on the internet. and it's accessible to these scam artists. >> reporter: that's what mark of central florida sails happened to him, making him wonder, at

. >> reporter: the calls to cindy gervais of new orleans started long after she and her husband had taken out and paid off an online loan. but she was told, falsely, she still owed more. >> and that i was a no-good, deadbet. that i would have the worst -- i would spend the night in jail and my family wouldn't be able to get me out. >> reporter: so she sent them more than $1,800 to pay off a debt she did not owe. authorities say the scammers buy their victims names and financial information from dishonest online payday loan brokers. >> that information is on the internet. and it is accessible to she's scam artists. >> reporter: federal authorities say the calls can be traced to a major organized crime group in india, where call centers have targeted hundreds of thousands of americans. abc news went to one of the companies alleged to be involved, where employees denied any knowledge of the scam, but refused to let us inside. >> can you please switch off this? >> reporter: federal authorities say the scam would not be possible without the help of american frontmen, including kirit patel of t