The US government has confirmed that at least two Guantanamo Bay detainees released by President Barack Obama's administration, and at least two more released by George W. Bush's administration, "returned to terrorist activities" in the first six months of 2016. That's according to a so-called "recidivism report" released Wednesday by the Office of the Director of National Intelligence (ODNI).

The report, which covers a six-month period that ended July 15, does not publicly identify the former detainees, nor does it provide details about the activities in which they allegedly engaged. The report's definition of "terrorist" or "insurgent" activities includes "conducting a suicide bombing, financing terrorist operations, recruiting others for terrorist operations, and arranging for movement of individuals involved in terrorist operations," but not incidents where ex-detainees have made "anti-US statements or propaganda."

The ODNI is required to publicly release an unclassified version of the report biannually. The latest version found that of the 161 former detainees released during Obama's presidency, just nine — 5.4 percent — are "confirmed" to have reengaged in terrorism. By comparison, George W. Bush's administration released 532 detainees, and 113 of those — 21.2 percent — were "confirmed" to have reengaged. Several of the ex-detainees transferred while Bush was in office were killed in targeted drone strikes during Obama's presidency.

Last June, the Washington Post reported that the Obama administration suspected at least 12 former detainees have launched attacks in Afghanistan against US or allied forces, killing about a half-dozen Americans.

The conclusions in the ODNI's report are based on discussions between the directors of National Intelligence, the CIA, and the Secretary of Defense. The latest report shows that the findings are not always clear-cut: The number of detainees released by the Obama administration who were "suspected" — but not "confirmed" — of reengaging in terrorist activities was revised down from 12 to 11 after the government found that a former detainee was no longer suspected of recidivism. The Defense Intelligence Agency also suspects five additional detainees of re-engagement, but that conclusion isn't shared by the other intelligence agencies.

The new report also corrects a "coding error" from a recidivism report released last March. The US now says three detainees who were suspected of re-engagement were killed, not four.

In order to "confirm" that a former detainee has reengaged in terrorism, the report says the US requires "a preponderance of information" that shows an individual is "directly involved in terrorist or insurgent activities." The baseline for "suspected" recidivism involves "plausible but unverified or single-source reporting indicating a specific former GTMO detainee is directly involved in terrorist or insurgent activities."

Of the 532 detainees released by the Bush administration, 75 are suspected of returning to terrorism. The report says that based on "trends" over the past 11 years, "some detainees currently at [Guantanamo] will seek to reengage in terrorist or insurgent activities after they are transferred."

"While enforcement of transfer conditions may deter re-engagement by many former detainees and delay re-engagement by others," the report said, "some detainees who are determined to re-engage will do so regardless of any transfer conditions, albeit probably at a lower rate than if they were transferred without conditions."

The ODNI's report was released shortly before the House of Representatives voted 244-174 in favor of a bill that seeks to prohibit the federal government from using funds to transfer any more detainees out of the detention facility. The White House has already said Obama would veto the legislation.

Twenty of the remaining 61 Guantanamo detainees have been cleared for transfer to other countries. The Pentagon is expected to move them off of the naval base by the end of the year. The Obama administration has released 32 detainees so far in 2016.

Shuttering the notorious detention facility was a pledge the president made during his first weeks in office. He says he still believes he can accomplish the goal, but doing so would require transferring at least some of the remaining prisoners to the US — a move that would be almost impossible because it requires congressional approval. Still, during a summit with Southeast Asian officials in Laos this month, Obama said he's not ready to "concede" that Guantanamo will remain open.

Follow Jason Leopold on Twitter: @__JasonLeopold

CORRECTION: This story originally reported that two detainees released this year had been confirmed of returning to terrorist activities. It's four detainees, and the date of their release is not publicly known.

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