WASHINGTON (AP) — An American aid worker kidnapped by militants more than six years ago in West Africa has been freed, his wife and a senior military official said Monday, but the circumstances of his release were not immediately clear.

Aid worker, Jeffery Woodke, was kidnapped in Niger in October 2016 and is later believed to have been taken to neighboring Mali.

His wife, Els Woodke, of McKinleyville, California, said she had been notified by the US government that her husband had been released. She said that she was told that he was in Niamey, the capital of Niger.

“He is safe,” she said in a telephone interview. “I still don’t know if he is healthy.”

A US official confirmed that Mr. Woodke was in Niamey and said he was undergoing medical evaluation. Another senior administration official who briefed reporters confirmed Mr. Woodke’s release and said the United States had not paid a ransom or made any other concessions. The official spoke on condition of anonymity as part of the standard rules for safety briefings.

Jake Sullivan, the president’s national security adviser, thanked Niger “for their help in bringing him home.” in a Twitter message.

A French security official confirmed that another hostage had also been released: Olivier Dubois, a French journalist who went missing in Mali in April 2021, and was later seen in a hostage video broadcast by an al Qaeda affiliate there.

Mr. Woodke’s release ends an ordeal in which US officials at times believed a dangerous military operation would have been required to free him. There is no indication that the US mounted such a bailout.

But the kidnapping of Mr. Woodke played a role in a fatal ambush by US soldiers in West Africa.

In October 2017, US soldiers rushed to a location in the Niger bush after intelligence officials intercepted a cell phone signal from a terrorist known as Doundoun Cheffou, a high-ranking lieutenant of a former al Qaeda affiliate. who had sworn allegiance to the Islamic State. .

Mr. Cheffou was being tracked by US intelligence agencies because of his seniority with the terrorist group and because he was suspected of playing a role in Mr. Woodke’s kidnapping.

The nightly raid failed to find Mr. Cheffou, but hours later four of the Americans were killed in an ambush near the town of Tongo Tongo.

The senior administration official who briefed reporters said that while Woodke was captured in Niger, it appears he was taken across its borders to other nations. The official said Woodke was released outside Niger, in an area in the west of the country that includes Mali and Burkina Faso.

The official did not specify which organization had taken Woodke, calling it a hostage-taking “network.”

The official added that another prisoner captured in Niger, whom the official did not identify, was released by the same network about six months ago.

The official said that efforts to free Mr. Woodke had been underway for a long time and that Secretary of State Antony J. Blinken, who stopped in Niger during a visit to Africa last week, had “confirmed” the release. while I was there.

The official said that France, which is Niger’s former colonial ruler and maintains ties to its government, also played an important role in securing Woodke’s release.

Rukmini Callimachi and michael crowley contributed reporting.