EXCLUSIVE: GOP Sens. Lindsey Graham, R-S.C., and Ted Cruz, R-Texas, joined forces to send a message to Department of Homeland Security Secretary Alejandro Mayorkas that they have "grounds for impeachment" if he fails to act swiftly in correcting his "gross dereliction of duty" at the southern border.
In a letter to Mayorkas on Tuesday evening exclusively obtained by Fox News Digital, the senators compiled data produced by U.S. Customs and Border Protection (CBP) that show that the crisis at the southern border has deteriorated since Mayorkas took office 19 months ago.
"This is gross dereliction of duty and, if not corrected swiftly, could provide grounds for impeachment," the senators wrote.
"Your failure to faithfully enforce this nation’s immigration laws and willful blindness to the very real humanitarian crisis at our southern border amounts to a gross dereliction of duty and a violation of your oath of office," the senators wrote.
"Despite the heroic efforts by the men and women of Border Patrol, who operate with very little support from Washington, D.C., you have failed to achieve any semblance of operational control of the southern border," they continued.
According to CBP, there have been "over 4.4 million illegal crossings, including over 3.5 million apprehensions by CBP and at least 900,000 gotaways, who evaded apprehension."
In addition to the record-high border crossings and migrant encounters, the senators charge Mayorkas with enabling a drug production and smuggling enterprise by Mexican cartels with China-supplied drug ingredients that directly contributed to the "fentanyl-fueled" opioid pandemic that killed 108,000 Americans last year.
Fentanyl, which has become the leading cause of death of Americans ages 18 to 45, is "streaming across our southern border," the senators wrote, noting that just last month 2,287 pounds of fentanyl were seized by CBP agents — enough to kill more than 500 million people.
"Drug cartels produce bulk amounts of fentanyl in Mexico, using the Chinese-supplied ingredients, and smuggle the drug across the U.S.-Mexico border," the senators explained in their letter. "This amounts to a multi-billion dollar business for transnational criminal organizations, who then launder the money out of the United States and back into China."
"This lucrative illicit enterprise continues to thrive—while Americans die—all because DHS has ceded control of our southern border to the cartels for political gain," they continued.
The senators also warned that the "chaos" at the southern border "presents a prime opportunity for terrorists to enter the United States undetected," especially following the "disastrous withdrawal" of U.S. troops from Afghanistan last year, noting that border patrol agents have apprehended at "least 78 individuals on the Terrorist Screening Database" so far in fiscal year 2022 — more than twice as many apprehended in the past five fiscal years combined.
"It is a near certainty that terrorists have already entered the United States undetected, taking advantage of the lenient border policies you have put into place," the senators wrote. "It is only a matter of time until we will see an attack on American soil from such terrorists."
Both Graham and Cruz, who serve on the Senate Judiciary Committee, prior to this letter have implored Mayorkas and the White House numerous times to make changes and address the border crisis.
Collectively, the Republican senators have visited the border six times in the last two years. Neither President Joe Biden nor "border czar" Vice President Kamala Harris have visited the border since taking office, the senators noted in their letter.
"You have stated multiple times that "the border is secure" even as the crisis rages on," the senators wrote.
"Vice President Harris apparently shares this same delusion. Perhaps if she or President Biden would visit the southern border and actually see the unending surge of illegal immigration, illicit drugs and human suffering, the White House would feel differently," they state.
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The White House has repeatedly denied claims of a crisis at the southern border.
Most recently, Harris twice declared that the U.S. southern border is "secure" during an interview last month, despite a record number of migrants crossing into the country.
"We fully expect that in a few months’ time a Republican-led Congress will hold you to account for your willful negligence regarding the security of the southern border and the safety of the American people," the senators conclude.
DHS did not immediately respond to Fox News Digital's request for comment on the letter.