President Donald J. Trump used a rally in Florida to voice his frustrations with the influx of migrants at the southern border. "It's an invasion," he said to the crowd of supporters Wednesday evening. But also noteworthy was what he didn't say: the president did not condemn an incendiary remark from an audience member who suggested shooting migrants. Instead, he made a joke about it.

Mr. Trump was talking to a crowd of thousands in Panama City Beach about the U.S.-Mexico border and characterized obstacles U.S. Border Patrol agents face in preventing migrants from entering the country. "You have 15,000 people marching up and you have hundreds and hundreds of people, and you have two or three border security people that are brave and great," he said.

"Don't forget, we don't let them use weapons," he said of the border patrol. "We can't. Other countries do. We can't. I would never do that."

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He asked his base, "But how do you stop these people?"

One attendee loudly responded, "Shoot them!" The crowd laughed. (Watch the video in the player above.)

Mr. Trump grinned, shook his head and said, "Only in the Panhandle you can get away with that statement. Only in the Panhandle!" His supporters roared in cheers.

Some Democrats and immigration advocates decried President Trump's remarks on social media.

The House Homeland Security Committee, which is led by Democrats, called it "horrifying" and shared video of the moment on Twitter.

Here’s the video of that horrifying moment from last night.👇🏽 https://t.co/VesCB1Lm52 — House Homeland Security Committee (@HomelandDems) May 9, 2019

"This is what endorsing and promoting violence against immigrants looks like. Disgusting and shameful," tweeted the National Immigration Law Center, a nonprofit dedicated to advancing and defending rights of low-income immigrants.

During the rally, Trump also slammed Democrats, whom he accused of wanting "more and more" in federal aid for Puerto Rico, and mocked candidates running for the Democratic presidential nomination in 2020.

The president's visit to Florida came as Democrats in Washington are warning of a "constitutional crisis." Earlier in the day, the president claimed executive privilege over special counsel Robert Mueller's entire report and its underlying documents, and the House Judiciary Committee voted in support of holding Attorney General William Barr in contempt of Congress.