On Thursday morning, federal authorities in Texas unsealed criminal charges against dozens of people who are accused of being part of a “transnational criminal organization” that allegedly victimized tens of thousands of people and yielded hundreds of millions of dollars in losses.

The indictment was filed against 61 people and includes charges of conspiracy to commit identity theft, impersonation of an officer of the United States, wire fraud, and money laundering. Of those people, 20 were arrested Thursday in the US.

The suspects are believed to have orchestrated an incredibly large series of phone-based scams that lasted for years. According to prosecutors, the suspects would call victims, impersonating Internal Revenue Service and United States Citizenship and Immigration Services officials, and would then demand payment through debit cards or wire transfers. If victims didn’t pay up, the callers threatened them with arrest, deportation, or heavier fines. There were also related scams involving fake payday loans and bogus US government grants, according to the criminal complaint.

Earlier this month, hundreds of people believed to be associated with a similar scam were arrested across nine locations in Mumbai, India.

The criminal complaint briefly summarizes many cases, referring to victims only by their first name, last initial, and city.

For example, one man, Suresh M. of Hayward, California, ended up paying $136,000 through 276 MoneyPak cards to people he believed were from the IRS and who claimed that he had outstanding tax violations.

“This indictment will serve to not only seek the conviction of those involved but will send a message around the world that no one is safe from prosecution for participating in such pervasive transnational fraud schemes,” US Attorney Kenneth Magidson said in a statement. “We are extremely vigilant when the names of US government agencies are used to perpetuate fraud for the purpose of victimizing so many innocent American citizens.”

Magidson's office did not immediately return Ars' request for further comment.

Anyone who believes they may be a victim of fraud or identity theft in relation to this investigation or other scam phone calls may contact the Federal Trade Commission via this website.