Four individuals on the Federal Bureau of Investigation’s Terrorist Screening Database have been arrested at the southern border.

“The Customs and Border Protection agency confirmed to Congress today that four people arrested at the southern border since Oct. 1 match names on the FBI’s Terrorist Screening Database,” a congressional aide briefed on the correspondence told Axios.

In the group, three people arrested were from Yemen and one was from Serbia.

The four arrests are “more than the number of similar people taken into custody during recent full fiscal years, according to the source,” Axios adds.

Throughout the entirety of 2018, six people from the Terrorist Screening Database were arrested.

The revelation follows Todd Bensman’s National Pulse commentary and podcast highlighting how porous border have been exploited by terrorist groups across Europe.

“As discussed at length in America’s Covert Border War, The Untold Story of the Nation’s Struggle to Prevent Jihadist Infiltration, Europe’s experience showcases a new terrorism travel phenomenon on the world stage: that malevolent long-haul migrants from countries rife with Islamist terrorist organizations now routinely cross land borders of western nations and do so far less noticeably when high volumes of benevolent economic migrants have overwhelmed border management systems,” he notes.