U.S. officials are still unsure whether an Al Qaeda-linked terrorist was killed by an airstrike in Libya last summer, according to a published report.

Mokhtar Belmokhtar and several other militants were the target of the June 14 airstrike outside the eastern city of Ajdabiya.

At the time, one senior defense official told Fox News that the airstrike "likely" killed Belmokhtar, while another official said, "We are confident it was a good strike."

But according to The Washington Post, enough officials have expressed doubt about Belmokhtar's fate to prevent the Obama administration from formally declaring him dead.

"We took a shot, but we could never really confirm his demise," one U.S. official told the Post.

The case is an example of the difficulties U.S. forces face when targeting terrorists in places like Libya, where there is little troop presence on the ground and intelligence networks are tenuous.

In the days after the attack, two groups linked to militants in Libya released statements listing the names of those they claimed were killed in the airstrike. Belmokhtar's name did not appear in either statement. Officials also noted that Belmokhtar's followers did not issue any statements celebrating his martyrdom.

However, the Post reported that enough circumstantial intelligence supported Belmokhtar being killed in the airstrike for the State Department and FBI to remove him from their respective most-wanted lists. However, officers in the U.S. Africa Command were less confident and demanded more intelligence.

In recent months, Belmokhtar's organization, Al-Murabitun, which calls itself "Al Qaeda in West Africa" named him leader of their jihadist activities and the group has been blamed for several deadly attacks since last fall. Among them are the Nov. 20 attack on an upscale hotel in Mali that killed 20 people, including an American development worker and last month's attack on a hotel and cafe in Ouagadougou that killed 30 people, including an American missionary.

Following the Mali attack, French Defense Minister Jean-Yves Le Drian told a French television station that he believed Belmokhtar was still alive.

Belmokhtar, a veteran of the 1990s civil wars in Afghanistan and his native Algeria, was wanted in connection with a 2013 attack on a gas plant in Algeria that killed 38 hostages, including three Americans.

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