U.S. Customs and Border Protection (CBP) began to physically test prototypes of southwestern border walls this week, according to a department spokesman.
Interested in Mexico?
Add to Mexico as an interest to stay up to date on the latest news, videos and analysis of Mexico from ABC News.
The beginning of the official trial period was November. 27, but physical evidence began on Monday, said Carlos Diaz, head of CBP's public affairs branch for the southwest border.
The construction of eight wall prototypes in the San Diego sector was completed on October 26. Six companies were chosen to build eight sample walls: four made of concrete and four built of "other materials".
President Donald Trump turned the southern border wall between Mexico and the United States into the letter of presentation of his presidential campaign. "Building the Wall" became a familiar chant at all the rallies of the Trump campaign, and stopping illegal immigration was one of the candidate's main selling points.
The prototypes are the first steps in CBP's efforts to build a wall, although administration officials have acknowledged that a future wall is unlikely to extend from "sea to bright sea," despite the initial promise of Trump to cover the entire border.
Last week, CBP officials began training, safety and protection procedures, as well as programming to establish the tests.
Physical tests will include attempts to scale and inflict prototypes. The officers will use elements such as pneumatic hammers, saws and hydraulic tools to try to break the prototypes.
During the acquisition process, the companies were required to build the walls at a depth of at least 6 feet. The depth of the walls was evaluated during the construction process, according to Díaz.
The eight prototypes were required to be between 18 and 30 feet high and were designed to avoid illegal crossings.
The prototypes were built side by side of the current secondary wall in San Diego, which already has a primary and secondary barrier.
Officials say that current barriers must be modernized.
Over the past three years, the existing infrastructure in San Diego has been violated almost 2,000 times, according to Roy Villareal, the deputy chief patrol agent of the San Diego sector.
He said that this is a "testament" to the need for new wall structures.
"If you come back in the late 80's, the limit was completely invaded, there were daily robberies, rapes, assaults, car thefts, high-speed chases, dead people along the border in amazing numbers," said Villreal. , in declarations to ABC News in front of the prototypes. "All that has been reduced as a result of the investment in border security, which has been reduced as a result of what you see here today."
However, critics and Democratic lawmakers say the wall is a waste of time and money.
"Let me be clear: Trump's border fence is a waste of money and I will block funds for it," Sen. Kamala Harris, Democrat of California, said in a July tweet.
Rep. Barbara Lee, a California Democrat, tweeted in March that "the Trump Wall is a waste of money and an insult to our values", with the hashtags "#NoBanNoWall" and "#JointSession".
"Across the Southwest, border residents and local stakeholders such as mayors and sheriffs are firmly opposed to President Trump's insanity, based on economic, environmental and humanitarian impacts," said Lorella Praeli, director of Immigration policies and campaigns in the Civil Liberties Union in a July statement.
On Tuesday, CBP announced that during fiscal year 2017, there were a total of 310,531 arrests by the United States Border Patrol nationwide, the lowest total number in at least 17 years.
Of those apprehensions, almost 98 percent were along the southwest border.
In August, the Department of Homeland Security (DHS), which oversees CBP, issued an exemption to certain laws, regulations and other legal requirements to expedite the prototype construction process.