Almost 10000 South Africans have discovered they are fraudulently married since 2001.
Figures from the Home Affairs Department show that 9796 people, most of them women, have reported being fraudulently married to foreigners.
Most cases occur in Gauteng. This year alone, the department was alerted to 1616 cases in the province by last month.
Eastern Cape followed with 120 reported cases. KwaZulu-Natal had 97, Limpopo 41, Mpumalanga 21, North West 33, Free State 14, Northern Cape 18, Western Cape 10 and 13 marriages in unknown provinces were reported.
So far, 1983 cases have been reported this year. Of those, 1589 marriages have been deleted from the department's records while 325 cases have been referred to court.
Only 16 men had their marriages annulled, and only one man features in the 325 cases referred to court.
Mantshele Tau of the Department of Home Affairs said younger women were prone to fall for the financial rewards of a fraudulent marriage to a foreigner.
"Unfortunately, illegal immigrants target young women with the promise of money. But we are dealing with that phenomenon."
He said some people would go through with a marriage and then claim it was fraudulent after the "husband" had received his citizenship.
"In such cases, we do not get involved even if people come and report that they were married without their knowledge. They just have to go through the process of divorce."
Tau conceded that corrupt officials in the department married people without their knowledge. Once detected, internal disciplinary action is taken against the officials, including dismissal.
Tau said the Check your Marital Status Campaign that Home Affairs Minister Nosiviwe Mapisa-Nqakula launched in 2005 had helped the department deal with the problem.
"At least, now people can walk into any branch of the department and check their status."
He said the department had completed investigations into 8683 cases since 2001 and that 1113 were still being probed.