RNC 2024 Day 3 updates: JD Vance touts working class roots in debut as VP nominee

The title for this session is "Make America Strong Again," with speeches centered on foreign policy and national security.

Speakers have discussed China, Russia and energy policy.

But immigration, specifically border security, has stoked the most audience reaction -- with attendees often waving "Mass Deportation Now!" signs.

"Send them back!" chants started as Texas Gov. Greg Abbott spoke about bussing migrants to Democratic cities.

Texas Gov. Greg Abbott touted President Trump's border policies and his own as the largest border state governor in the country. The governor received a raucous reception at the RNC.

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Abbott says Trump will secure border

Texas Governor Greg Abbott touted former President Trump’s border policies and his own as the largest border state governor in the country. The governor received a raucous reception at the RNC.

ABCNews.com

He defended his orders that the Texas National Guard install razor wire across parts of the Texas border and his policy of bussing migrants out of Texas and north. (A narrowly divided Supreme Court in January sided with the Biden administration in a tense, ongoing dispute over the Texas-Mexico border and razor wire fencing installed by the state that had prohibited federal border agents from performing their duties.)

"The president's most sacred duty is to secure our country," Abbott said. "Joe Biden deserted his duty," the governor argued.

"It is time to restore order at the border, to rid our streets of crime and chaos; it is time to secure our nation by returning Donald Trump as president of the United States of America," he said.

As Jim and Sue Chilton took to the stage to talk about their experience as Arizona ranchers operating near the border, chants of "build that wall" erupted in the arena.

Building a border wall from coast to coast was a key priority for Trump in his first term, though he implemented just roughly 450 miles of barriers -- much of which was upgrading existing barriers that already existed.

Republicans have been bashing the Biden administration's immigration policies, arguing that more undocumented immigrants have been entering the country.

Last month, Biden issued an executive action that limits the number of migrants who can claim asylum between ports of entry at the southern U.S. border.

Since then, the number of encounters at the southern border have decreased by more than 50%, according to government data.

The Department of Homeland Security said it removed and returned more than 50,000 individuals to more than 100 countries since the new rule went into effect.

Border Patrol agents made roughly 83,536 migrant apprehensions in between ports of entry at the southern border in June, the lowest since January 2021, according to government data.

-ABC News' Mireya Villarreal