The Homeland Security Department inspector general issued an urgent recommendation to abandon plans to reinstate an electronic system to process naturalization applications, warning of "alarming security concerns."

DHS' Electronic Immigration System, or ELIS, has technical flaws that could cause it to grant citizenship to people even if they're "ineligible or pose national security threats" as a result of insufficient vetting, according to an alert issued Monday by the agency's Office of Inspector General.

The OIG recommended U.S. Citizenship and Immigration Services stop a plan to reactivate ELIS. Ordinarily, the OIG would have waited for months to issue a full report after the audit was complete, but it published the urgent recommendation Monday so USCIS would take corrective action before returning to ELIS, according to a press release from that office.

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The system has not been used since August 2016 because of security concerns. During that time, USCIS relied on legacy systems but had plans to return to ELIS in late January 2017.

The OIG previously identified several security problems in November, including that ELIS often experienced outages, “problems with system interfaces” that resulted in decreased productivity, and potentially erroneously issued almost 20,000 green cards.

Several problems persist, according to a new audit beginning in December. Those flaws include that "printed certificates sometimes included incorrect names or lacked mandatory data such as photos or country of origin, rendering them invalid," naturalization cases got stuck in the workflow, the system canceled applicant interviews, and ELIS moved forward cases with "incomplete or inaccurate background and security checks."

Though OIG's review is still in the early stages, it has already found "significant operational and security issues that pose grave concern and merit ... attention and corrective action.”

OIG recommended DHS do a risk-based analysis first before reinstating ELIS.

"[W]e strongly advise USCIS leadership against the premature return to electronic processing of naturalization applications until corrective actions are taken and these persistent issues are resolved,” Inspector General John Roth said in a statement. The OIG plans to issue a more comprehensive report in spring 2017.