(NEXSTAR) — During the first presidential debate of 2024, President Joe Biden and former President Donald Trump sparred over their immigration and border security policies.

Biden called out Trump for separating migrant families at the U.S.-Mexico border, while Trump argued that “we had the safest border in history” under his presidency.

The Biden administration had reversed some of Trump’s measures that were intended to prevent migrants from arriving at the border, including legally.

Still, only 3 in 10 U.S. adults approve of Biden’s approach to immigration, according to a new poll from The Associated Press-NORC Center for Public Affairs Research.

Trying to gain more ground on the issue, Biden claimed Thursday night that Border Patrol endorsed him and his “position” on immigration.

The Border Patrol did not endorse Biden, though a union for its agents endorsed a bipartisan Senate proposal that the White House negotiated with Republicans.

The National Border Patrol Union reiterated their stance in a short statement posted to X, formerly Twitter: “To be clear, we never have and never will endorse Biden.”

During Thursday night’s debate, Trump also leaned into making a link between crime and immigration — a key claim for Republicans ahead of November’s election — making a generalized assessment of immigration based on isolated crimes.

There have been recent high-profile and heinous crimes allegedly committed by people in the country illegally. But FBI statistics do not separate out crimes by the immigration status of the assailant, nor is there any evidence of a spike in crime perpetrated by migrants, either along the U.S.-Mexico border or in cities seeing the greatest influx of migrants, like New York. Studies have found that people living in the country illegally are less likely than native-born Americans to have been arrested for violent, drug and property crimes.

Immigration has risen as a national priority, not just among Republicans. In a Nexstar survey conducted this week, 24% of 1,109 respondents who self-identified as undecided voters viewed immigration and border security as the second-most important issue ahead of election day.

The Nexstar survey was distributed to users of Nexstar Media Group websites across the country. It is not scientific in nature and instead showcases a gauge of our viewers’ sentiments. More than 9,000 people participated in the survey from June 24 to June 25.

The Associated Press and The Hill contributed to this report.