Armed smugglers allegedly associated with the Gulf Cartel were responsible for the onslaught of automatic fire that endangered the lives a Border Patrol Marine Unit in early August, as it policed the banks for drug smugglers and human traffickers along the Rio Grande Valley River, in Texas.

Department of Homeland Security investigators recently uncovered that it was to prevent the Border Patrol boat from trampling or breaking an underwater pulley line devised by the cartel to transport large quantities of cocaine into the United States, according to a For Official Use Only law enforcement sensitive document obtained by SaraACarter.com.

U.S. Customs and Border Patrol agents were not aware at the time why the assault was launched on their Marine Unit, according to a Border Patrol official who spoke to this news outlet. The U.S. Border Patrol agents, assigned to the Rio Grande City Station Marine Unit, were patrolling the Rio Grande near Fronton, Texas. They reported they were fired upon from the Mexican riverbank and witnessed four subjects with automatic weapons who shot over 50 rounds at them. The boat was hit several times but no one on board was injured, according to the CBP at the time.

Moreover, a Border Patrol official in the area told this reporter that agents operating in the Rio Grande Valley only discovered the circumstances regarding the incident from another DHS agency last week and not from Border Patrol management.

“We only found out from another agency,” said a Border Patrol official working in the Texas region. “Management doesn’t even pass this shit off to us. Kept us in the dark and it would have been nice to know from a safety perspective.”

DHS officials could not be immediately reached for comment.

The Gulf Cartel was utilizing the underwater pulley system to move the shipments without detection across the river when the Marine Unit entered their area, the law enforcement sensitive document stated. Further, the smugglers feared the pulley line would be cut and the contraband would be lost, a U.S. official told this reporter.

“(Redacted) claims to have overheard conversations with the Border Patrol Marine Unit,” the law enforcement sensitive document said. “Members of the Cartel del Golfo (CDG) were attempting to smuggle a large quantity of cocaine near Fronton, Texas.”

According to the report a source with knowledge had told the Border Patrol that the Gulf Cartel “had set up an underwater pulley system from Mexico to the U.S. banks to cross the bundles of cocaine without detection. While (Gulf Cartel) members were attempting to smuggle in the cocaine, other members set up to scout for USBP Marine units reported a Border Patrol vessel headed in the direction of the smuggling attempt.”

As the cartel members began to “recover the bundles of cocaine on the pulley line, members of CDG began to fire at the USBP marine unit,” the report states. “CDG fired upon the Marine unit to prevent it from crossing and breaking the pulley line.”

The Gulf Cartel, also known as the Cartel Del Golfo, is a top Mexican narco-trafficking organization that wages bloody battles for territory along the U.S. Mexico border against other top drug organizations, like Sinaloa Cartel and Los Zetas. The group is estimated to move hundred of millions of dollars in drugs and other types of contraband into the United States.

The Gulf Cartel is considered one of the most dangerous cartels in Mexico.

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