The K3 visa is issued by the United States Citizenship and Immigration Services as a marriage visa. It allows people to enter and stay in the United States so they can be with their spouses. The K3 visa is a non-immigrant visa, but it may be converted to a Green Card within three months if the holder completes the proper application. Due to its nature, this visa has a high rate of fraud; people often abuse the system to obtain Green Cards and live in the United States.
Verify that your information is correct. If you suspect that a marriage is a sham marriage and that the two parties are abusing the system to obtain a Green Card, make sure that your accusations are worth investigating. The Department of Homeland Security handles all visa fraud investigations and its time needs to be spent wisely. All accusations of fraud must be investigated, so make sure that you understand the situation at hand and that your accusations are not being made out of speculation, a rumour or a "feeling."
If the couple is currently in the United States, notify the Department of Homeland Security's United States Immigration and Customs Enforcement. The Department of Homeland Security handles many cases of visa and marriage fraud. You can notify them by dialling 1-866-DHS-2-ICE (1-866-347-2423).
If the spouse has yet to arrive in the United States, notify the United States Embassy, in the region where he or she is applying, of the fraudulent activity. When you notify the embassy, the immigration officer handing the case will investigate the visa application closely and exercise extra caution when issuing the K3 visa.