WESLACO - A drug linked to countless deaths nationwide is for sale in the Rio Grande Valley.

The RGV is seeing the effects of the fentanyl drug hiding in plain sight.

Fentanyl is an opioid that's causing a problem in the United States, as well as locally.

On Dec. 13, three people were arrested in connection with a sale of fentanyl in the Valley.

According to the criminal complaint, they were trying to sell over a kilo of fentanyl to an undercover DEA agent.

Rudy Maldonado heads the agency in McAllen.

"We've had several cases. In fact this year, we've seen fentanyl here in the Valley. We've seen a lot of it in pill form also," says Maldonado.

He says they're working several cases involving this drug.

The agency itself went before a senate committee hearing to speak on the dangers of the drug.

They spoke on the potency of the drug and concluded that two-milligrams is considered a lethal dose.

The DEA says the opioid comes through Mexico and through the hand of Cartel del Jalisco Nueva Generacion.

In Texas, it comes through Laredo which has a heavy presence of the cartel on the Mexican side.

The DEA says the Gulf Cartel isn't trafficking the drug, but that changed with a new alliance described by former FBI Agent and Security Expert Arturo Fontes.

"There's members of the Gulf Cartel that have traditionally been working with Cartel de Jalisco, and some of these people are people that live in the Valley and have connections with the Gulf Cartel. And, there's liasion contacts that deal directly with the leaders of the Cartel de Jalisco in Guadalajara,”says Fontes.

Splinters from Jalisco work with the Gulf Cartel, which is how the drug has arrived to the RGV.

It was laced over heroin or cocaine, but cartels seized the business opportunity with the recent prescription abuse in the U.S.

"Counterfeit pills are probably the most abused drug in the United States right now. So, they started pressing fentanyl into pills, whether it's Oxy, Xanax, Ritalin, or hydrocodone," Maldonado says.

The pills look like the drugs some already abuse, but without a federal lab running a test on it, there's no way users will know whether those pills also contain a deadly dose of the opioid.

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