WATCH: GOP senators begin boat tour of Rio Grande as part of border visit
Cruz posted a video from the Rio Grande overnight that appears to show human smugglers on the Mexican side of the river.
"That's Mexico right over there, and you can see there are three smugglers right there," Cruz is heard saying in the video.
WATCH: Ted Cruz with live footage from the border
He also said those smugglers were taunting the senators on the U.S. side.
Cruz called on Pres. Joe Biden's administration to strengthen the border and reverse policies that Cruz says is fueling a surge at the border.
WATCH: Sen. Cruz accuses Biden of hiding border facilities
Meanwhile, Biden says he will not allow unaccompanied children to stay on the Mexican side where they are hungry and exposed to the elements.
When asked if those children will be allowed to stay in the U.S., Biden said that will be determined on a case-by-case basis.
The delegation also visited overrun holding facilities where the senators claim to have seen mothers and children cramped into small outdoor areas with dirt floors.
SEE RELATED STORY: Out of space: More emergency sites opening to handle influx of migrant children
"This is a humanitarian crisis, this is a public health crisis," Cruz said. "The illegal immigrants who are being released, they are testing positive for COVID-19 at a seven times higher rate than the American population, and it is a national security crisis."
When a reporter asked Biden if what's happening inside the facilities is acceptable to him, he said, "That's a serious question, right? That's why we're going to be moving 1,000 of those kids out quickly."
SEE RELATED: U.S. trying to dissuade migrant travel to ease growing border crisis
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