Los Angeles County Sheriff’s Department officials issued a warning regarding phone scammers on Monday following the arrest of two people who allegedly posed as government officials in order to steal $16,000 in gift cards.

Victims lost about $4,000 per transaction, District Attorney John Weller said at a press conference on Monday morning, noting that most of the targets were elderly and located in Northern Los Angeles County.

The two suspects, a couple from Georgia, face charges of extortion and attempted extortion. The investigation began March 12 and ran through late April.

“The message that we’re trying to get across today is that you should never take a phone call asking for money from a government office,” Department Chief Patrick Nelson said. “I know for a fact that the IRS won’t call you, and I can certainly tell you that the LA county sheriff’s department will never call you and ask you to provide money in the form of gift cards.”

Police have raised concerns over this issue in the past. Last year, USC’s Department of Public Safety warned international students on campus that phone scammers would pose “as officials from their home governments or as immigration officers.”

Carlisle, when reached by phone on Monday, confirmed phone scammers continue to be an issue for students on campus.