KABUL, Afghanistan - Spec. Bowe Bergdahl, the only known U.S. soldier held captive in Afghanistan, appears briefly in a newly released Taliban video standing next to a smiling insurgent commander who once threatened to kill him.

The 24-year-old from Hailey, Idaho, has bags under his eyes and what appears to be an abrasion on his left cheek in the footage. The video was the fourth to appear since he was captured nearly 18 months ago, and was provided to reporters Wednesday by IntelCenter, a private, U.S.-based organization that tracks Islamic extremist activities and communications.

His parents, Bob and Jani Bergdahl, have declined to speak with reporters throughout the ordeal, but an Idaho National Guard spokesman, Col. Tim Marsano, said Wednesday they had confirmed that the man in the video was their son.

"They responded that it was him, based on the screen shots," Marsano said. "It's been an extremely difficult year and a half. Without any concrete news, every day brings more challenges. They do continue to take some comfort in the support they've gotten, from the community, their family, and friends."

A NATO spokesman, Brig. Gen. Josef Blotz, said the coalition was not sure whether the footage was new. Bergdahl is seen wearing an Afghan-style, lightweight tan shirt, suggesting that the video was shot during warmer weather.

"We are still investigating this case and hope Bowe Bergdahl is still fine," he said.

Bergdahl has been held by the Taliban since June 30, 2009, when he disappeared in Paktika province in eastern Afghanistan.

According to the SITE Intelligence Group, which also tracks Islamic extremist activities, Bergdahl is standing next to Sangin Zadran, a senior official in the al-Qaeda linked Haqqani network in Paktika. In July 2009, Sangin's spokesman said in a telephone interview that Berghdal would be killed unless the United States stopped strikes in Ghazni province's Giro district and Paktika's Khoshamand district.

Bergdahl, who is seen in just a few seconds of footage that includes a montage of past extremist attacks and news events, nods occasionally as if acknowledging another speaker and often looks down at the ground.

The 69-minute video, produced by Manba al-Jihad, a video production group of the Haqqani network, was released on the website of the Afghan Taliban on Dec. 2 but appeared on jihadist forums last month, according to SITE.

Bergdahl has appeared in three other videos that the Taliban released, on July 18, 2009, Dec. 25, 2009, and April 7.

Separately, two NATO service members died Wednesday after an insurgent attack in southern Afghanistan. The coalition did not disclose their nationalities or details about their deaths. So far this month, 12 members of the NATO coalition have been killed in Afghanistan. At least 671 have died this year.