Acting Immigration and Customs Enforcement (ICE) Director Todd Lyons warned Tuesday of an increasing risk of a potential terrorist attack within the United States, citing the growing number of illegal immigrants operating heavy trucks on American highways.

Lyons, speaking publicly about national security concerns, said the Biden administration’s border policies have allowed millions of “unvetted” illegal immigrants to enter the country, some of whom have obtained commercial driver’s licenses (CDLs) issued by sanctuary states such as California and New York. ICE recently arrested 146 illegal immigrant truck drivers on Indiana highways.

“We don’t know what they’re carrying across state lines in an 18-wheeler, terrorists will stop at nothing to harm the United States, and it is well within the realm of possibility that some of these trucks… could be carrying toxic chemicals, bombs, or God knows what,” Lyons explained.

The issue of illegal immigrants obtaining CDLs has drawn national attention in recent months, particularly after a fatal crash in Florida involving an Indian national who made an illegal U-turn in an 18-wheeler, killing three people. It was later revealed that the driver had failed the commercial driver’s license test ten times in Washington state but was still issued a CDL there and later in California. Reports also showed the driver was not proficient in English and could not read road signs.

Other accidents have since highlighted similar concerns involving drivers who spoke little to no English, raising questions about how they are being licensed to operate large commercial vehicles. 

“There’s no good checks and balances to be perfectly honest with you,” said Lewie Pugh, Executive Vice President of the Owner-Operator Independent Drivers Association, according to The Daily Wire. “A lot of states allow third party testing to do the CDLs and I would say that’s how most of these people get through.”

“It all comes down to cheap labor, they want the cheapest people behind the wheel and unfortunately by doing that … what we are getting now is carnage on the highway,” Pugh added.