The incident happened in Hudspeth County, east of El Paso, yesterday, Zapata County Sheriff Sigifredo Gonzalez, Jr, chairman of the Texas Border Sheriffs Coalition, told 1200 WOAI news.
Gonzalez says it started when Hudspeth County deputies and Texas State Police officers spotted three vehicles they suspected were transporting drugs south of Sierra Blanca, not far from the Rio Grande.
"They followed the vehicles," Gonzalez said. "One of the vehicles had a blowout, and 1400 pounds of marijuana was found in that vehicle. The driver absconded back into Mexico. The other two vehicles headed towards the riverbank. One of them crossed back into Mexico, and the third got stuck in the riverbed.
"At that time, officers saw several persons clad in BDU uniforms, BDU clothing, on this side of the river, in what appeared to be a Humvee type vehicle with what officers thought was a fifty caliber machine gun. The load of marijuana was unloaded by the persons in these uniforms and the vehicle was then set on fire."
'BDU' or 'Battle Dress Uniform' is the military term for 'camouflage uniform.'
Gonzalez says the men in the SUV and the uniformed men 'went back towards Mexico.'
Agent Andrea Simmons of the FBI in El Paso told 1200 WOAI news the bureau is 'aware' of the incident but is not investigating.
"At this point no federal laws that we investigate were violated," she said. "We are not involved."
Gonzalez says this is 'not an isolated incident.'
"If you don't live along the river, if you don't live in this area, you don't know what's happening here," he said.
Gonzalez elaborated on several similar incidents which have happened along the Texas Mexico border recently, all involving men wearing what appeared to be Army uniforms armed with automatic weapons, who appeared to be helping drug smugglers.
"These incidents are happening," he said.
The Mexican government is downplaying the incidents, and has said the men involved are not Mexican soldiers.
"When you see a Humvee vehicle with a fifty caliber machine gun on it, this leads you to believe this is not a vehicle being used by the drug lords, but in fact is part of the Mexican military. I think of course the Mexican government knows about this."
He says it would be highly unlikely that the men did not know they were in the United States.
"There is a river here. It is not possible not to know you have crossed the river and are in the United States," he said.