Two suspects were collared Tuesday at Eddy's Arena on State Route 82 near the Nogales International Airport where agents discovered about 5,000 pounds of marijuana.

The Santa Cruz County Metro Task Force seized 256 bundles of weed.

The Santa Cruz County Metro Task Force seized 256 bundles of weed stacked in a barn at the arena and more than $73,000 in cash, said Sheriff's Lt. Gerry Castillo.

He said that after obtaining a search warrant from Justice Court Precinct No. 2, officers also seized two bullet-proof vests, a safe, six semi-tractors, one trailer, four horse trailers, two all-terrain vehicles, a Nisan four-door pick-up with Mexico plates, a 2006 Ford Dually pick-up truck, a 1987 Chevrolet Suburban and a 2007 Ford F-250 King Ranch crew-cab pick-up.

As of Wednesday afternoon, the safe had not been opened, Castillo said.

He noted that this is the largest load seized by the agency since it netted about 7,000 pounds of marijuana in the North River Road area about two years ago and arrested four suspects.

Sheriff Capt. Ruben F. Fuentes gave the following account of Tuesday's bust:

At about 5:30 p.m., agents noticed a Chevrolet Suburban in the Kino Springs area east of Nogales. "It looked like it was weighed down and loaded."

The agents followed the Suburban to the Elias Ranch where the roping arena is located.

Officers apprehended the owner of the ranch, Heriberto Elias-Aguirre, 51. He was charged with possession of marijuana for sale and conspiracy. Jesus Artalejo, 55, who attempted to flee the scene and later told officers he is a truck driver for Elias, also was apprehended. He was charged with possession of marijuana for sale.

Castillo noted that a woman identified as Elias' wife was at the home, but was not arrested. The operation had agents out at the ranch for several hours with some clocking out after 5 a.m.

In other enforcement activities, Fuentes said that a resident of Yuma, who owns a home in Rio Rico, called the sheriff's office Monday to say he suspected illegal activity as transpiring at a house he owns on Villa Salvaza.

Upon investigating, the officers came upon 44 undocumented migrants in the home. The case was turned over to the Border Patrol.

Earlier that day, the Border Patrol called the sheriff's office to report the death of a teen-aged illegal migrant at Milepost 19 of Arivaca Road near the Sopori Ranch.

Marco Antonio Garcia Trejo, 18, was traveling with a group of illegal migrants including his brother when he began to feel ill, Fuentes said.

"His brother went to get help from Border Patrol, but by the time they got back, he was deceased," he said.

Fuentes said that the group had been trekking through the desert for about three days.

"With the clampdown in the Aliso Springs area, they're walking further into the desert and taking riskier routes," said Fuentes.

The Aliso Springs area, north of Tubac, has been a hotbed of human-smuggling activity and authorities have heightened patrols of the area, he explained.