If you got a gift card recently, LA officials say to check the barcode immediately

As the holiday season continues, Los Angeles officials are urging retailers and shoppers to double-check their gift cards for these warning signs.

Last week, LA County Supervisor Hahn allegedly purchased a Vanilla Visa gift card at a CVS for her nephew's birthday only to find that the card had been drained before he could use it.

Supervisor Janice Hahn held a press conference Thursday addressing the gift card scam circulating in the Southern California area.

The scam, known as "gift card draining," works in two ways. In the first instance, scammers attach a barcode from a card they already have to an unsold gift card still in store. When someone buys the tampered card and loads money onto it, they are actually loading money onto the scammer's card.

Miami Hialeah, Florida, Lowe's Home Improvement, hardware store, gift card display Google Play, Apple, Hulu, AMC. (Photo by: Jeffrey Greenberg/Universal Images Group via Getty Images)

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In the second instance, a scammer steals the details of a legitimate gift card and then places it back on a store rack. That scammer can then track when the card is bought and loaded, so they can quickly drain the money.

"I am fortunate, what I lost on this gift card, I was easily able to repay in cash to nephew," said Hahn, "But I am worried about the people who are barely scraping by who can't afford to be ripped off."

Hahn suggested retailers display gift cards behind a glass case or service desk while these scams continue, or better train checkout clerks to recognize fake barcodes and add warning signage on gift card displays.

"I am calling on retailers like CVS, Target, Walgreens and others, to take immediate steps to protect their own shoppers from these scams," said Hahn at the press conference. "It should not be up to consumers to defend themselves from scams when you have the power to prevent them altogether."