Video captured on the border between Arizona and Mexico’s Sonora state shows two young men scaling the international border fence. (Carolina Rocha and Azteca Noticias)

Debate has raged in recent months about the size and practicality of Donald Trump’s proposed wall along the U.S.-Mexico border.

The wall’s proposed height — gleaned from the Republican front-runner’s speeches and interviews — has ranged from 30 to as high as 55 feet.

The goal of the wall, Trump has said, is to curb illegal immigration and drug smuggling. But a newly released video shot by a Mexican film crew filming along the border in Nogales, Ariz., last month, captures just how elusive that goal can be, even with a massive obstruction already in place.

Carolina Rocha, a reporter for Mexico’s Azteca Noticias, was filming a segment for a story about the U.S. Border Patrol’s use of force when her crew was interrupted by two men scaling a border fence to arrive on the American side in broad daylight, according to the Associated Press. The men — wearing black T-shirts and jeans — had bulging packs strapped to their back, leading many observers to speculate that they were smuggling drugs.

The men were able to use gaps to grip the nearly 30-foot-high wall, which is already considered one of the most guarded borders in the United States, according ABC affiliate KABC.

Once on the ground, men scurried for cover, coming increasingly close to the journalists until they realized they were being filmed.

“Don’t record,” one of the men says, according to the AP.

Rocha refused and told the men she was just doing her job, the AP reported.

“It was shocking,” she told the AP.  “This is happening in front of me? And we didn’t stop recording.”

After angrily waving at the TV crew, the two men — who had been communicating with someone using a radio or cellphone — retreated back to the wall. Within seconds, they had climbed over the top and disappeared back onto the Mexican side of the border.

“There are already about 650 miles of fencing, including the steel fence that divides the sister cities of Nogales in Arizona and Mexico and ranges from 18 feet to 26 feet tall,” according to the Associated Press. “Much of the border fence was built in the past 15 years as immigration surged. The cost has been in the billions.”

The writer of a New York Times op-ed called the barrier a “monument to futility.”

“A climber with a rope can hop it in less than half a minute,” Lawrence Downes wrote in 2013. “Smugglers with jackhammers tunnel under it. They throw drugs and rocks over it. The fence is breached not just by sunlight and shadows, but also the hooded gaze of drug-cartel lookouts, and by bullets.

“Border agents describe their job as an unending battle of wits, a cat-mouse game with the constant threat of violence,” Downes added.

Such was the case during the illegal crossing caught on camera. Rocha told the AP that three U.S. Border Patrol trucks were within yards of the two men, but no agents approached.

Border Patrol spokesman Mark Landess told the AP that the area is a hotbed for drug smuggling, and it’s not uncommon for smugglers to scale the fence.

Landess added that it’s impossible to know why agents didn’t pursue the men or if they even spotted them.

“They might be waiting for something else to happen,” he said. “There’s no way to make an educated comment on that.”