President Donald Trump stops in Yuma ahead of campaign rally in downtown Phoenix Tuesday

Posted at 4:24 PM, Aug 19, 2017
and last updated 2017-08-22 20:34:44-04

President Donald Trump stopped in Yuma ahead of his rally at the Phoenix Convention Center Tuesday.

Air Force One touched down at Marine Corps Air Station Yuma around 1:30 p.m. Arizona time.

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Trump visited the base, which is also a hub for U.S. Customs and Border Protection. Trump inspected equipment used on the southern border, including a drone, helicopter and boat, which were on display in a hangar at the base. At one point, Trump was spotted patting the side of the drone.

Trump also shook his head as he was shown a series of everyday objects, such as a fire extinguisher, that had been refashioned to secretly transport drugs across the border. After the tour, Trump spent about 20 minutes greeting service members in the grueling, 106-degree heat, signing caps with his "Make America Great Again" campaign slogan and posing for selfies on the tarmac just steps from Air Force One.

It had been a decade since a president had visited Yuma. He visited for about an hour. 

A previously planned visit to tour a section of the U.S. border with Mexico at the San Luis II port of entry was not on the President's official schedule, and he did not leave the grounds of MCAS Yuma during his stop.

CNN, citing a source familiar with the situation, said the border visit was scrapped due to security concerns. When asked to specify the nature of the threat, a Secret Service spokesperson told CNN the agency does not comment on its protective operations.

Administration officials briefing reporters on the trip said the area had seen a 46 percent drop in apprehensions of people attempting to illegally enter the U.S. between Jan. 1 and July 31, compared with the same period in 2016. None of the officials would agree to be identified by name.

In fact, immigrant traffic around Yuma has dramatically slowed over the past dozen years. Once a hotbed for illegal immigration, the Border Patrol sector covering Yuma now ranks among the lowest in the Southwest for apprehensions and drug seizures.

There were some 138,000 apprehensions in 2005. The number had dropped to 14,000 by last year.

The White House says the president plans to hire 5,000 agents to protect the border, but Yuma alone has only sworn in 9 officers in a month. 

RELATED: Phoenix Mayor Greg Stanton not happy about President Trump's rally plan

Trump is trying to shift the focus to his core campaign theme of getting tough on immigration after rankling some of his most loyal supporters with his decision, announced Monday, to maintain to a U.S. military presence in Afghanistan. They also were unhappy about the recent ouster of conservative Steve Bannon as White House chief strategist.

Bannon had made it his mission to remind Trump of what his most fervent supporters want from his presidency, and some conservative strategists have openly worried that without Bannon around, Trump will be too influenced by establishment Republicans on issues such as Afghanistan policy.