(DAILYCALLER) — Thousands of green cards are missing because U.S. Citizenship and Immigration Services (USCIS) officials apparently sent them to the wrong addresses, jeopardizing national security, according to a Department of Homeland Security (DHS) Office of Inspector General (IG) report made public Monday.

“It appears that thousands of green cards have simply gone missing,” DHS Inspector General John Roth said in a news release. “In the wrong hands, green cards may enable terrorists, criminals, and undocumented aliens to remain in the United States. It is vital that USCIS ensure better tools and procedures are in place to mitigate such risks.”

The USCIS in the last three years received more than 200,000 reports from approved applicants claiming their cards were never delivered, the IG found. Monday’s audit — a follow-up to a March IG report saying USCIS officials sent hundreds of green cards to the wrong addresses — revealed “the problem was far worse than originally thought,” the IG said.

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