Donald Trump reacts as reporters yell questions to him after he stated that he believes President Obama was born in the United States at a campaign event at the Trump International Hotel in Washington, D.C., Sept. 16. (Mike Segar/Reuters)

The Department of Homeland Security's inspector general on Monday released a report detailing at least 858 immigrants from countries that pose national security threats or their neighbors who have mistakenly been granted citizenship. They were naturalized despite being ordered to be removed from the country, because the government couldn't match their identities to their removal orders.

The report lands at a potential inflection point in the presidential election. Donald Trump has long carved out a strong position against admitting Syrian refugees and called for "extreme vetting" of other immigrants — calls he ramped up still further after this weekend's terrorist attacks in Minnesota, and New York and New Jersey, both of which appear to have been perpetrated by Muslim immigrants (one from Somalia and one from Afghanistan).

Trump's campaign is already promoting the report. It's unlikely to stop anytime soon.

The report, it should be noted, doesn't say the immigrants were all criminals. But there's plenty for the Trump campaign to work with here.

From the Associated Press's report:

The report does not identify any of the immigrants by name, but Inspector General John Roth's auditors said they were all from "special interest countries" — those that present a national security concern for the United States — or neighboring countries with high rates of immigration fraud. The report did not identify those countries.

Here are a couple other key points from the report itself:

  • "[U.S. Citizenship and Immigration Services] granted U.S. citizenship to at least 858 individuals ordered deported or removed under another identity when, during the naturalization process, their digital fingerprint records were not available. The digital records were not available because although USCIS procedures require checking applicants’ fingerprints against both the Department of Homeland Security’s and the Federal Bureau of Investigation’s (FBI) digital fingerprint repositories, neither contains all old fingerprint records."
  • "Later, [Immigration and Customs Enforcement] identified missing fingerprint records for about 315,000 aliens who had final deportation orders or who were criminals or fugitives, but it has not yet reviewed about 148,000 aliens' files to try to retrieve and digitize the old fingerprint cards."
  • "Under the [Immigration and Nationality Act], a Federal court may revoke naturalization (denaturalize) through a civil or criminal proceeding if the citizenship was obtained through fraud or misrepresentation. However, few of these individuals have been investigated and subsequently denaturalized. As it identified these 1,029 individuals [a number that was reduced to 858 after finding duplicates], OPS referred the cases to ICE for investigation. As of March 2015, ICE had closed 90 investigations of these individuals and had 32 open investigations. The Offices of the United States Attorneys (USAO) accepted 2 cases for criminal prosecution, which could lead to denaturalization; the USAO declined 26 cases."

Trump has been making the case that the bureaucracy is simply too dense and faulty to adequately vet both Syrian refugees and potential immigrants from countries with a history of terrorism. He has called for a ban on Syrian refugees and "extreme vetting" of all immigrants from specific countries where terrorism is a concern — though he hasn't delineated which countries would be included or just how much of his previous blanket ban on all Muslim immigrants remains intact.

And this report completely plays into his hands on that second count. The Department of Homeland Security is disclosing that it not only mistakenly allowed certain immigrants due for deportation to stay and become citizens; it allowed immigrants from countries that pose threats to remain.

Expect to hear plenty more about this one in the days ahead.