An Al Qaeda affiliate in the Arabian Peninsula threatened to execute an American hostage in Yemen in a video released Thursday.

The hostage, identified as Luke Somers, was captured in September 2013 in front of a supermarket in the Yemeni capital of Sanaa. The 33-year-old American, a British-born photojournalist, was doing freelance work for the Yemen Times and, since his capture, Yemeni journalists have been holding sit-ins in Sanaa to press the government to seek his release.

In the video, obtained by the SITE Intelligence Group -- a U.S. terrorism monitoring group -- Washington was given unspecified demands to meet or the man would be killed in three days.

The U.S. Embassy in Sanaa would not comment on the demands, but in the past, Al Qaeda in the Arabian Peninsula has asked for money.

The video mimicked some of those used by Al Qaeda rivals from the Islamic State group, which has beheaded several American and British hostages in the aftermath of a summer blitz that captured much of Iraq and Syria.

Somers was among a group of hostages who were the objective of a joint rescue mission by U.S. operation forces and Yemeni troops last month that freed eight captives in a remote corner of Yemen's Hadramawt province.

Sources tell Fox News that Somers was moved before the raid along with retired Yemeni Intelligence official Rashid al-Hebshi, who was found dead Thursday in the Hadramawt area.

The Pentagon confirmed Thursday the hostage rescue mission last month in Yemen failed to liberate Somers because he was not present at the targeted location.

The Pentagon press secretary, Rear Adm. John Kirby, said in a brief written statement that the U.S. government was acknowledging the attempted rescue of Somers.

Kirby said the Pentagon wanted to "provide accurate information" in light of the fact that the rescue attempt has been widely reported. 

A Yemeni official said an American journalist and a Briton were moved before the raid.

The video shows a local Al Qaeda official speaking of America's crimes against the Muslim world. He urges the U.S. to meet demands, which he says the country is "aware of."

Al-Ansi criticizes U.S.-led airstrikes against the Islamic State group and President Obama for his "latest foolish action," referring to the "failed operation" in Hadramawt. He says an "elite group of mujahedeen," or holy warriors, were killed in the U.S. raid.

He also warned the U.S. against more "stupidities," referring to future attempts to rescue hostages.

Al-Ansi gives the U.S. three days to meet Al Qaeda's demands or "otherwise, the American hostage held by us will meet his inevitable fate," without elaborating or explicitly saying they would kill their captive.

Then Somers is shown, giving a brief statement in English and asking for help.

"It's now been well over a year since I've been kidnapped in Sanaa," Somers said. "Basically, I'm looking for any help that can get me out of this situation. I'm certain that my life is in danger. So as I sit here now, I ask, if anything can be done, please let it be done. Thank you very much."

Somers, who attended Beloit University in Wisconsin, came to Yemen in 2010 on a teacher’s visa. After not being able to find work in education there, he switched to a career in photojournalism and become one of the most active photographers during the Arab Spring uprising in 2011.

Somers later worked as a translator and interpreter in the press center of the National Democratic Council, which is focusing on the transition of Yemen from the Arab Spring protest period to a new government.

Those who knew Somers described him as “cool” and “polite” with an interest in Yemen, sources told Fox News. But Somers was also said to be a bit tired of the ongoing political turmoil in the country.

Abduction of foreigners has been common in impoverished Yemen, troubled both by Al Qaeda and the advance of Shiite rebels, but while kidnapping for ransom was common in the past, threatening a hostage's life appears to be a shift in the Al Qaeda branch's tactics.

On Thursday, Yemeni security officials said the body of a Yemeni hostage, who had been held captive with Somers, was found in the district of al-Qatn in Hadramawt late Wednesday.

The officials, speaking on condition of anonymity in line with regulations, identified the man as Rashid al-Habshi and said the Al Qaeda Yemeni branch had recorded his purported confession of helping Americans in carrying out drone strikes against militants.

The U.S. drone strikes, targeting suspected militant gatherings, have become increasingly unpopular in Yemen due to civilian casualties.

Fox News' Greg Palkot and The Associated Press contributed to this report.