More than two dozen men and women are accused of arranging or participating in marriages with Bulgarians to help the foreigners evade U.S. immigration laws, a federal prosecutor said Thursday.

The scheme, which involved U.S. citizens being recruited and paid to marry Bulgarians, appears to have started in 1997, Assistant U.S. Attorney Kevin McDonald said. He would not comment on money amounts.

"The allegations are that this was a ring, a conspiracy, to engage in fraudulent marriages," he said.

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A federal indictment charged 13 Bulgarians and 15 U.S. citizens with conspiring to arrange or participate in the marriages. Nine were still being sought. More than a dozen also faced an additional marriage fraud charge.

"They did not reside together as husband and wife, and had no intention of residing together," the indictment states.

The marriages occurred in South Carolina, where the U.S. citizens were recruited, and Georgia, the indictment stated. Some of the Bulgarians were arrested in Boston, Chicago, Stamford, Conn., and Portland, Maine, McDonald said.

If convicted of the conspiracy charge, each person would face up to five years in prison.

Many suspects appeared in court Wednesday and were released on bail, McDonald said.

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