MCALLEN, Texas – The three Texan’s kidnapped and killed in Mexico in October had ties to Mexican cartels, according to a leaked Homeland Security document obtained exclusively by Breitbart Texas.

Mexican news outlets had previously reported the Texans were innocent victims.

A woman and her two brothers from the border town of Progreso, Texas -- along with a drug cartel member -- went missing on October 13, near the Mexican border town of Control. Their decomposed bodies turned up on October 29, not far from where they went missing. The four bodies were identified as Erica Alvarado, her two brothers Alex and Jose Angel, and her boyfriend Jose Guadalupe Castaneda.

Breitbart Texas previously reported that soon after the Texans went missing, Mexican news outlets -- under the direction of the Gulf Cartel -- began running a series of articles blaming the kidnapping and disappearance of the group on an elite police force called Grupo Hercules. Grupo Hercules was started by the Matamoros Mayor Leticia Salazar in order to fight drug cartels. Breitbart Texas investigated the case and published an exclusive article about the Narco-media campaign and the victim’s ties to the Gulf Cartel.

The intelligence report obtained by Breitbart Texas confirms this.

Erica Alvarado and her two brothers were apprehended for attempting to smuggle drugs on October 7, 2013. At the time of the arrests, Alvarado was driving her Dodge Ram pickup truck with her two children and her brothers in a drug smuggling attempt. They tried to cross the Falfurrias Border Patrol Checkpoint with close to 50 pounds of marijuana hidden in the truck’s spare tire, the leaked intelligence report shows.

After their arrests, Border Patrol agents turned them over to the U.S. Drug Enforcement Administration for further investigation. The U.S. Attorney’s Office, however, declined to prosecute the case.

The report additionally sates that Castaneda had been convicted three times for entering the country illegally and was involved with Mexican organized crime but does not state the group he was tied to or his rank. The intelligence report also states that the murder could have been committed by a drug cartel or Transnational Criminal Organization rather that a police force.

"Information obtained from HSI Brownsville...indicated that Castaneda was possibly associated to TCO ["Transnational Criminal Organization"] activity in northern Tamaulipas," the document stated. It went on to say, "It should also be noted that Alvarado's arrest for smuggling marijuana in October 2013 indicates that she was involved in smuggling activities but it is unknown as to the duration of her involvement in border crosser smuggling."

Breitbart Texas had previously published that Castaneda was a local crime boss in Control who went by the nickname “Negrito” and had been in charge of dealing with stolen fuel. His death was linked to a falling out with a cartel boss named Ariel “El Tigre” Trevino, and not to an elite police force going rogue.

Soon after the bodies were discovered, Lyrik Dog -- a group of Narco hip hop artists who sing praises about cartel members -- posted on Youtube.com a rap video praising the “Three Brothers”. The video sings about the three brothers smoking drugs and drinking alcohol as they risked their lives for “La Compania” which is a term used to describe the Gulf Cartel. Shortly after it was posted, the video was removed.

Mexico’s Attorney General’s Office started an investigation into Grupo Hercules, while Mexican news outlets repeatedly castigated Salazar and Hercules before any charges were ever filed. To date, no charges have been filed against the police force or Salazar.

Follow Breitbart Texas Managing Director Brandon Darby on Twitter @BrandonDarby and Ildefonso Ortiz on @ildefonsoortiz.Intel Report by BreitbartTexas