(NewsNation) — Border Patrol agents have caught seven potential terrorists trying to enter the U.S. from Mexico since the beginning of May, sources with U.S. Customs and Border Protection (CBP) told NewsNation.

With the latest arrests, border patrol has recorded 103 apprehensions of individuals on the terror watchlist at the southern border since October — up from 98 during all of last year. All of those people were caught trying to cross the border between ports of entry.

On Saturday, five men on the federal terror watchlist were caught illegally crossing the border in the Tucson Sector, sources confirmed. Those men, who were all non-U.S. citizens, were arrested just days after the pandemic-era health policy known as Title 42 was lifted.

Border authorities in California also apprehended an Afghan national on the watchlist last week.

Another man on the watchlist, a Colombian national, was caught in the Yuma Sector on May 1, sources told NewsNation.

Douglas Nicholls, the mayor of Yuma, said he’s worried how many others on the watchlist escape undetected.

“If there’s one, there’s more than one,” said Nicholls, who pointed out that Mexican drug cartels manage traffic through the area.

The terror watchlist is the U.S. government’s database that contains sensitive information on terrorist identities. The individuals on the list include “known or suspected terrorists” as well as “additional individuals who represent a potential threat to the United States, including known affiliates of watchlisted individuals.”

As illegal border crossings have increased in recent years, border patrol has seen a significant uptick in watchlist encounters of non-U.S. citizens.

From 2017 to 2020, border patrol agents recorded just 11 encounters with individuals on the watchlist who were caught crossing the southern border between ports of entry.

Even with the increase over the past two years, potential terrorists represent a small fraction (less than .01%) of all border patrol encounters.

After surging shortly before Title 42 ended last week, daily migrant encounters at the southern border have dropped about 50% in recent days.

The decline comes shortly after the Biden Administration announced a new asylum policy that closely mirrors a Trump-era rule.

Under the new policy, migrants who don’t first seek protection in a country they passed through or haven’t applied online will be denied asylum in the U.S.