Nov. 30 (UPI) -- The Afghan national accused of shooting a two National Guard troops while they were deployed in Washington, D.C., was part of an elite CIA unit in Afghanistan, members of which have struggled to adjust to life in the United States.

The alleged shooter, Rahmanullah Lakanwal, 29, worked with the CIA in Afghanistan as part of a "zero unit," or national strike unit, who worked with the American military to track down high value Taliban targets in Afghanistan.

Many members of these units, whom NBC News reports are among the most vetted Afghans who worked with the U.S. military, were evacuated in 2021 when the United States pulled out of Afghanistan because they were expected to targeted for retribution by the Taliban after it retook power.

"He was brought into the country by the Biden administration through Operation Allies Welcome. And then, maybe vetted after that, but not done well, based on what the guidelines were put forward by President Biden," Homeland Security Secretary Kristi Noem said Sunday on ABC News' "This Week."

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