EXCLUSIVE: Sen. Tim Scott, R-S.C., issued a dire warning about the U.S. border crisis during an event at the Republican National Convention (RNC) on Wednesday.
"We have men from Yemen, Iran, Iraq, Afghanistan, Lebanon crossing…our southern border," Scott said during a South Carolina GOP delegation breakfast. "I believe we have sleeper cells in this nation as a result of Joe Biden."
"We've got to fire him," Scott added as the room applauded in response.
Scott's warning of terror threats at the border is not new – FBI Director Chris Wray told Congress in March that there is "no doubt" criminals have come across the southwestern border, though no specific threats were outlined.
Wray said at the time, "There is a particular network where some of the overseas facilitators of the smuggling network have ISIS ties that we’re very concerned about, and that we’ve been spending an enormous amount of effort with our partners to investigate."
His speech comes as the RNC is expected to kick off its third day of programming, with Wednesday's theme focused on national security.
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Border security is likely to be a central topic of the evening as Republicans continue to hammer the Biden administration for its handling of the migrant crisis at the southwestern border.
"How many of y'all have a back door?" Scott asked the audience. "You see, my back door is locked. Anybody disagree with that?"
Members of the crowd shouted "no" in response.
"If you won't leave your back door unlocked at night, why would we leave the back door of the greatest nation on the planet unlocked?" Scott asked.
He continued to warn about the threat of foreign nationals from other continents, "If we, and I believe that we do, if we have a national security risk that's across our southern border, think about this…we have 100,000 Chinese nationals that have crossed our southern border."
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And while Republicans and some moderate Democrats have criticized the Biden administration's approach to the border crisis, Biden and his allies continue to accuse the GOP of derailing a bipartisan border security deal that Republicans said at the time did not go far enough.
Fox News Digital reached out to the White House for comment.
Fox News' David Spunt contributed to this report
