There's a new brand of kidnapping that's been sweeping Mexico and has been exported to Phoenix.

Investigators term it "virtual kidnapping."

The Immigration and Customs Phoenix division typically gets a report once a week of smugglers holding a hostage.

About a quarter of the reports are bogus, Assistant Special Agent-in-Charge Armando Garcia said.

Mexican extortion gangs find out when someone in the U.S. travels to Mexico and demand a ransom from the traveler's family.

Gangs know the traveler can't communicate with home, and gamble that threats will compel families to pay before they learn the traveler was safe.

In another version, con artists get hold of smugglers' lists of illegal immigrants, then call their families in the U.S. and demand ransom.

Often, immigrants are waiting to cross or on their way to a Phoenix drop house when the call comes.