At least 380 of the 580 individuals convicted of terrorism-related charges in the U.S. since September 11, 2001 are foreign-born, according to an analysis of Justice Department data conducted by the Subcommittee on Immigration and the National Interest.

“When compared with your Administration’s immigration policies, and bearing in mind the four major terrorist attacks in the United States in the last year alone, this inability to properly screen individuals from abroad and assimilate those we admit paints a striking picture,” Sen. Jeff Sessions (R-AL), the chairman of the Subcommittee, and Sen. Ted Cruz (R-TX) wrote in a letter to President Barack Obama dispatched last week and released Wednesday.

Of the 380 foreign-born individuals, at least 24 came to the U.S. as refugees and at least 33 were in the U.S. illegally on expired visas. According to the Subcommittee, at least 62 of the foreign-born terror convicts were from Pakistan, 28 were from Lebanon, 22 were Palestinian, 21 were from Somalia, 20 were from Yemen, 19 were from Iraq, 16 were from Jordan, 17 were from Egypt, and 10 were from Afghanistan.

Those 200 remaining individuals convicted of terror-related charges and not identified as foreign-born include 71 individuals who are confirmed natural-born U.S. citizens. The rest are unknown.

Sessions and Cruz received the Justice Department data after months of waiting and multiple requests — on August 12, 2015, December 3, 2015, and January 11, 2016 — to the Departments of Justice, Homeland Security, and State for the immigration histories of individuals implicated in terrorism since early 2014. According to the Subcommittee, the Justice Department did provide the list of 580 individuals convicted of terrorism or terrorism-related charges between September 11, 2001 and December 31, 2014.

The Justice Department directed the Subcommittee to DHS for the terrorism-convicts immigration histories, information DHS has yet to provide. While DHS has not turned over the immigration histories, the Subcommittee was able to conduct an open-source analysis of the names the Justice Department provided to pin the number of foreign-born individuals, in the list of 580, at some 380 people.

“Because we lack complete information for either list, the numbers are likely much higher,” Cruz and Sessions wrote in their letter to Obama. “And it is clear that these lists do not include cases that are sealed, have otherwise not been made public, or that have been handled strictly through civil immigration proceedings.”

Since the pair’s last request in January, the Subcommittee identified a total of 131 individuals implicated in terrorism since early 2014. Of those 131 new individuals implicated of terrorism at least 16 were initially admitted to the United States as refugees, and at least 17 of whom are the natural-born citizen children of immigrants.

“[T]hese data make clear that the United States not only lacks the ability to properly screen individuals prior to their arrival, but also that our nation has an unprecedented assimilation problem,” they added.

With the screening and assimilation issues, Sessions and Cruz expressed concern about the administration’s goal of resettling at least 10,000 refugees from the terror-hot spot of Syria.

“Given that we have already identified at least 40 individuals who were initially admitted to this country as refugees and who were subsequently convicted or implicated in terrorism – including an Iraqi refugee who was just admitted to the United States in 2012 and arrested in January of this year – it is clear that ensuring the proper screening of refugees is of the utmost importance,” they wrote.

The pair concluded by calling for the administration for a prompt response to their letter and initial inquiries.