WASHINGTON — Federal prosecutors brought charges Thursday against dozens of people accused of taking part in a massive international crime ring that relied on call centers in India to bilk thousands of Americans out of more than $300 million.

While the call centers have become a frequent annoyance for many US consumers, the Justice Department revealed a darker side to the operations in a thick indictment unsealed in Houston.

The operators of the scheme in India would pose as tax collectors, the police, or other authority figures in calling “targets’’ and demanding fraudulent payments for bogus debts, officials said. Nearly two dozen accomplices charged Thursday inside the United States would work to collect the money, prosecutors said.

In one case, an 85-year-old woman turned over $12,300 after she was threatened with arrest, officials said, while a California man turned over $136,000 to settle a bogus tax bill. About 15,000 victims in all were bilked, officials said.

Most of the people charged Thursday reside in India, but officials said they would seek to have India extradite as many as possible to stand trial in the United States.

New York Times