(NewsNation) — Concerns over known or suspected terrorists exploiting America’s immigration crisis are ramping up at the southern border following Hamas’ attack on Israel.

Since the Israel-Hamas war broke out, the number of migrants coming from “special interest” countries that neighbor Israel has increased, according to data from Customs and Border Patrol. These countries include Egypt, Syria, Yemen and Iran.

Last week, agents encountered 27 migrants from Syria, compared to the 21 migrants the same sector saw in all of September, CBP data shows.

During the same time, 18 people from Iran and three from Lebanon were stopped at the southern border.

In September, agents encountered 324 migrants from these countries at the southern border. Of those, 40% crossed through the Tuscon sector.

These countries are deemed “special interest” partly because they could pose a national security risk due to their proximity to the ongoing war.

“The difference between the United States and Israel is that Israel’s borders were overtaken by force. And because of a failure of intelligence, ours have been overrun by invitation,” said national security analyst Charles Marino.

Marino, a former Department of Homeland Security adviser, says the porous southern border has opened America’s doors to threats.

“Yes, of course, there are legitimate refugees that want and escape their countries because of what’s going on. However, as security practitioners here in the United States, we have to thoroughly vet people and be able to do so because we have to assume that they could be somebody with nefarious intentions. It may not sound fair in the way that I’m saying it. But it’s factual,” he added.

Marino says people from “special interest” countries must factor in what airport they can fly into and are likely to take the path of least resistance. But once they arrive at the southern border, the cartels decide who crosses into the U.S. where and when.