Video at the source link.~~~

Posted: Dec 16, 2013 9:15 PM PST Updated: Dec 16, 2013 9:15 PM PST
By Carissa Planalp, FOX News

NOGALES, Ariz. -- Ten tons of marijuana were found in a semi truck passing through the Mariposa Port of Entry earlier this month. It was the largest seizure of its kind, but numbers show most illegal pot is found in the desert.

Border Patrol agents were hot on the trail of a group of suspected illegal border crossers. They get to the top of a ridge and one of the suspected crossers was spotted.

Agents on all-terrain-vehicles catch up with the group with help from those on the look-out points.

Agents say these three will be arrested for crossing the border illegally. They were not found carrying drugs -- though most pot seizures are made out here.

I grabbed the numbers -- and look at how much marijuana is actually uncovered at border patrol checkpoints. More than 27,000 pounds this last fiscal year. Compare that to more than a million pounds in the entire sector-that includes the mountains and desert.

Agents in the field work in such challenging terrain that while driving out here to help other agents track down border crossers we had to stop the vehicle right here because of this steep washed out road and we had to continue on-on foot.

"Good vantage points for scouts to watch the Border Patrol," said Agent Peter Bidegain.

Bidegain says smugglers run entire networks out here using radios and this tall house just south of the border wall. "They have scouts positioned up in the house. You can see all the roads down below."

Agents can't be everywhere all the time -- so they use ground sensors and cameras to stop smugglers in their tracks. And they'll prove to be extremely useful since Border Patrol data shows more than 75 percent of all the marijuana smuggled through Arizona comes through the open desert.

http://www.myfoxphoenix.com/story/24...ugh-the-desert