SANTA FE, NEW MEXICO (REUTERS) - The prototypes for President Donald Trump's contest for a border wall near San Diego, California, were torn down on Wednesday (Feb 27) to make way for a new section of actual border fencing.

To the President's supporters, the eight 9m-high models were a symbol of his commitment to build a wall along the length of the United States-Mexico border to enhance national security.

To opponents, they were a waste of taxpayer money and an affront to Mexico and immigrants.

"Since the test and evaluation of these prototype models is complete, they have served their purpose and are now being removed," US Customs and Border Protection (CBP) spokesman Ralph DeSio said in a statement.

Using jackhammers, ladders and blow torches, military special forces and CBP special units spent weeks trying to go under, over and through the walls to test their strengths and weaknesses.

The tests of the prototypes, which Supervisory Border Patrol Agent Michael Scappechio of the San Diego sector said cost between US$300,000 and US$500,000 (S$404,000 and S$674,000) each to build, showed the effectiveness of the kind of steel post, or "bollard", fence that already exists along large sections of the border.

Now, a new 9m-high bollard fence is being built as a secondary barrier along a 22.5km section, behind an existing, 5m-high bollard fence, Mr Scappechio said.

The ability of agents to see through a barrier is crucial to their safety, and a fence made out of steel posts or "bollards" is easier to repair when breached and relatively cost effective, he said, while the 9m height is a deterrent to climbers.

The fence will also incorporate fibre optic sensors, Mr Scappechio said.