The Cameron County Sheriff's Office arrested three people on Monday accused of trying to smuggle drugs into a jail by hiding them in fake legal correspondence, according to a news release.

Investigators say inmate Victor Hugo Hernandez Jr. ran the operation. His wife, Kassandra Michelle Larose, allegedly prepared documents laced with a synthetic cannabinoid and mailed them to the jail. A second inmate, Michael Molina, was set to receive the drugs, according to authorities.

The group used fake attorney letterheads and different sender names to try to get past jail security, the news release stated.

Jail staff caught the scheme when they intercepted a suspicious letter before it was delivered that later tested positive for a synthetic cannabinoid, the news release stated.

All three suspects are charged with attempted prohibited substance in a correctional facility and engaging in organized criminal activity and remain jailed.

“We want the families and friends of those who are being held in our detention centers to understand one very important factor. If you conspire or assist in any way in introducing contraband into one of our detention centers, you will be arrested,” Cameron County Sheriff Manuel Treviño said in a statement.