Three L.A. County men have been charged in connection with a ring that kidnapped and held for ransom at least six people who were trying to cross into the United States illegally, federal prosecutors said Tuesday.

Edgar Lemus, 23, of Vernon; Francisco Hernandez Martinez, 20, of Vernon; and Junior Martinez, 23, of Watts are charged with conspiracy to launder money, the U.S. attorney’s office announced.

It wasn’t immediately clear whether they had attorneys to speak on their behalf.

The suspects pretended to offer assistance to people who wanted to cross the border from Mexico but instead held them for ransom and sometimes demanded additional money after receiving a payments, prosecutors said.

Prosecutors allege Lemus and the other two men picked up the ransom payments from relatives.

Lemus allegedly collected $19,000 in April at a Walmart store in South Gate from the husband of a woman who was kidnapped in Mexicali, authorities said.

“After delivering the payment, the kidnappers allegedly refused to release the victim and demanded additional payment,” the U.S. attorney’s office said in a statement. “After the victim’s husband told the kidnappers that they had made him crash his car and he was in the streets begging for more money, they stopped calling him.”

The woman was released a couple of days later, authorities said.

The other two men allegedly picked up ransoms at a Walmart and a Target store last month.

If convicted, each could face 20 years in federal prison.