Six American women have been charged with lying to authorities after being granted more than 40 marriage licences between them in an alleged immigration scam.
One woman had reportedly applied for 27 licences
The women had reportedly received more than $1,000 a time to marry illegal immigrants who could then obtain coveted green cards, New York officials said.
Green cards permit foreigners to live and work in the US, and entitle them to benefits from the US Government.
Marriage to an American is perhaps the easiest way to get one.
Clerks at the marriage registry in Manhattan said they grew suspicious after recognising the women's faces as they came in to the offices to apply.
Four women are in custody and two others are still being sought.
Not all the marriages went ahead.
Clerk Victor Robles said that he changed the city's system in order to search 10 years' worth of city records after he heard of one woman who claimed to have married six times, Reuters news agency reported.
He said he discovered that the women had applied for a total of 43 marriage licences to wed men from Pakistan, Ecuador, the Dominican Republic, Peru, Trinidad, St Lucia, India, and various African countries.
One woman alone had applied for 27 marriage licences in 20 years in Manhattan, and had also applied for licences in the US state of Florida, city lawyers said.
"They are nothing more than career brides," Mr Robles said.
"The women did not marry the men because of love, but because they were paid."
Mr Robles also said that because there are no links between city and state records and no national licence registry, anyone could abuse the system to obtain US residency and authorities would be none the wiser.