WESTMINSTER, Calif. (AP) _ More than 20 people were arrested in connection with vast credit card scams that allegedly enlisted Vietnamese immigrants with gambling debts to bilk banks and stores out of as much as $100 million.

Secret Service and FBI agents along with police from Orange, Los Angeles and Riverside counties raided homes and businesses in Southern California on Thursday. They carted away hundreds of thousands of dollars worth of gold bullion, jewelry, gambling chips and cash.

James E. Bauer, special agent in charge of the Secret Service's Los Angeles region, said the raids shut down two separate rings operating out of Orange County's ``Little Saigon'' district.

More arrests were expected. Losses from the scams could total $100 million nationwide, prosecutors said.

One woman, an Orange County employee, allegedly ran up a credit card debt of $615,000 while taking home only $1,000 a month from her job, according to bankruptcy records and Secret Service affidavits.

``This bust is unprecedented anywhere in the world,'' said Stan Belitz, director of security for MasterCard's Southern California region. ``This is the first time we've been able to convince prosecutors that this is a major problem.''

The nine-month investigation called ``Operation Repayment'' uncovered a scheme in which the ringleaders, sometimes posing as financial advisers, would get immigrants with gambling debts to run up big credit card debts buying merchandise and getting cash advances. They they would declare bankruptcy.

According to court documents, proceeds would be split among the participants, with the gambler applying his share to his debts.

If convicted of bank fraud, each defendant faces a possible sentence of 30 months in prison and a fine of $1 million on each count.