A video posted Monday on a Web site showed the beheading of a man identified as American hostage Eugene Armstrong.

The militant group led by Jordanian terror mastermind Abu Musab al-Zarqawi claimed responsibility for the slaying and said another hostage -- either another American, Jack Hensley of Marietta, or a Briton held by the group -- will be killed in 24 hours unless all Muslim women prisoners are released from U.S. military jails.

BILLY SMITH II/AJC (ENLARGE)
Cobb County Police block the way to the west Cobb County home of Jack Hensley, who was kidnapped in Baghdad on Thursday. Militants have threatened to kill Hensley and two other abducted Westerners if female prisoners in Iraq are not freed.
KHALID MOHAMMED/AP (ENLARGE)
Rashad Rashid cries while touching the remains of the truck his brother Ziad Rashid was killed in after an improvised explosive device went off under it on Sunday in Baghdad, Iraq.
EMAIL THIS PRINT THIS MOST POPULAR
Related: • Rundown of hostages taken in Iraq • Allawi touts stability, legitimacy, seeks resources to lead
IRAQ UPDATE • In another sign of instability 17 months into the U.S.-led occupation of Iraq, a suicide car bomb killed three people in Samarra — a northern city that U.S. and Iraqi commanders have portrayed as a success story in their attempts to put down the insurgency. • Lebanon's Foreign Ministry said Sunday that three Lebanese men and their Iraqi driver were abducted on the Baghdad-Fallujah highway Friday night. The four worked for a travel agency that has a branch in Baghdad, a Foreign Ministry official said. • U.S. warplanes and artillery pounded the insurgent stronghold of Fallujah late Saturday and early Sunday, killing four people and wounding six, hospital officials said. The military said it hit a checkpoint manned by militants linked to al-Zarqawi, the military said. • Four insurgents were killed when a bomb they were attempting to plant at the side of a road near the eastern Iraqi city of Suwayrah exploded shortly before midnight Saturday, a military spokesman said. GULF SUPPLIES & COMMERCIAL SERVICES • Where: Gulf Supplies & Commercial Services is based in Abu Dhabi, United Arab Emirates, and has offices throughout the Middle East including Aman, Baghdad, Kuwait City, Manama and Abu Dhabi. • Jobs: The company provides technical, logistical and operational support to the U.S. government and a number of companies in the rebuilding of Iraq. • Areas of expertise: Warehousing and logistics; construction, and heavy equipment leasing and sales. • Clients include: Bechtel, Northrop Grumman, Abu Dhabi Gas Industries, and the U.S. Department of Defense. Source: Company Web site: GSCS

"You, sister, rejoice. God's soldiers are coming to get you out of your chains and restore your purity by returning you to your mother and father," said a militant reading a statement in the video.

In Washington, a U.S. official, speaking on condition of anonymity, said Armstrong's body had been recovered, but the official would provide no information about where or when it had been recovered.

The taped beheading appears to be of Armstrong, but the CIA is still reviewing the tape to be sure, the official said.

The 9-minute tape was posted on a Web site used by Islamic militants after a 48-hour deadline set earlier by the group for the beheading of the three employees of a construction company abducted Thursday in Baghdad -- Armstrong, American Jack Hensley and Briton Kenneth Bigley.

The tape showed a man seated on the floor, blindfolded and wearing an orange jumpsuit with his hands bound behind his back.

Five militants dressed in black stood behind the man, four of them armed with assault rifles, with a black Tawhid and Jihad banner on the wall behind them. The militant in the center read out a statement, as the hostage rocked back and forth and side to side where he sat.

After finishing the statement, the militant pulled a knife, rushed to the hostage from behind and cut his throat until the head was severed.

"The fate of the first infidel was cutting off the head before your eyes and ears. You have a 24-hour opportunity. Abide by our demand in full and release all the Muslim women, otherwise the head of the other will follow this one," the speaker said.

He appeared to indicate the hostages would be killed one at a time and did not specify whether Hensley or Bigley would be next.

The voice of the militant sounded like past recordings attributed to terror suspect Abu Musab al-Zarqawi, whose Tawhid and Jihad group claimed responsibility for kidnapping Armstrong along with another American and a Briton.

The video surfaced after the expiration of a 48-hour deadline set by the group in an earlier statement. The militants had demanded the release of female Iraqi prisoners detained by the U.S. military.

In a previous videotape, the militants threatened to behead Jack Hensley of Marietta, Armstrong and Briton Kenneth Bigley on Monday unless Iraqi women are released from two U.S.-controlled prisons in Iraq.

The three construction contractors were snatched Thursday from their Baghdad home.

Hensley's wife and brother today made appeals to the kidnappers for mercy.

Patty Hensley appeared on the Arab television station Al-Jazeera and said her husband, like all Americans in Iraq, was there to help the Iraqi people.

In an interview today with ABC's "Good Morning America," Patty Hensley said her husband told her recently he was growing concerned because the Iraqi guards "were slowly and quietly leaving" the residence where he and two co-workers lived in Baghdad.

"They had guards who were there morning and night and just in the past -- little over a week -- something had started changing," Patty Hensley said in the interview. "The guards were not showing up for work. Or if they did, they had an excuse and they needed to leave. Something was wrong."

Jack Hensley wrote his wife recently that he feared he was being "staked out" and that Iraqi guards assigned as security feared for their own safety, said Jack Hensley's brother, Ty, on NBC's "Today" this morning.

"One told him, 'I have to leave this work, or they will kill me,'" Ty Hensley said.

Patty Hensley said she prays that his captors in Iraq will show him mercy and realize that he only wants to see their people succeed.

"My husband and the other two gentlemen absolutely loved seeing these people flourish," she said. "They could take their own lives in their own hands, they could go forward with it, and they were doing that.

Patty Hensley said she was advised not to speak to reporters, but she wanted her husband's kidnappers to know more about him and to realize that he doesn't wish them any harm.

"Let them come home," she said. "My God is praying for them. Allah is sending them a message, too, saying that to hurt these men is not going to serve any purpose. Just send them home. Send them home to their families, please." Patty Hensley said she's had difficulty explaining the crisis to her daughter, especially since her father is in Iraq to help the country.

"We raised our daughter to believe that everybody in the world is good," she said. "And you know, her first question to me was, 'Why would anybody hurt my daddy?' And I can't explain."

The family is drawing support from friends and neighbors who have visited their Marietta home.

Two women delivered a fruit basket Sunday afternoon adorned with a stuffed teddy bear and several bags of food to the family's home on Burnt Hickory Road, just west of the Kennesaw Mountain National Battlefield Park. Cobb County police officers are in the neighborhood to protect the family's privacy.

Ty Hensley told "Today" show's Katie Couric his brother "has an asthmatic condition and is probably having trouble breathing under the stress of his captivity.

His brother went to Iraq in February after failing to find construction work and needed money to support his wife and daughter, Ty Hensley said.

In his eight months there, he has worked repairing a water pipeline, a school and mosque. "He was well treated by the Iraqi people, which gave him a sense of comfort until recently," Ty Hensley said.

Hensley was shown on a videotape blindfolded, with a rifle pointed at the back of his head.

The British government and Bigley's brother, Philip, also appealed for their release in statements broadcast on the Arab satellite television station Al-Arabiya.

"Ken has enjoyed working in the Arab world for the last 10 years in civil engineering and has many Arabic friends and is understanding and appreciative of the Islamic culture," said Philip Bigley.

"He wanted to help the ordinary Iraqi people and is just doing his job," he said. "At the end of the day, we just want him home safe and well, especially for my mum Lil."

The Iraqi minister of foreign affairs, Hoshyar Zebari, told BBC television: "Really, our policy is not to negotiate with the terrorists."

Hensley, Armstrong and Bigley work for Gulf Supplies & Commercial Services, a construction firm based in United Arab Emirates working on rebuilding Iraq.

In a statement posted on its company Web site Sunday, GSCS officials said, "The safety of our co-workers is our highest priority. GSCS is working closely with the authorities to help resolve the situation and we plead with the captors for their immediate release."

Ty Hensley told Fox News Channel Sunday that "I know that the Iraqi people are good people, and they want him to be released.

"He was my, or is, my person who helped raise me. He coached my T-ball team growing up. He is not a person they should be killing to help their cause."

A woman who answered the phone at the Hensley residence Sunday afternoon told an Atlanta Journal-Constitution reporter the family had no further comment and asked that their privacy be respected.

Hensley, Armstrong and Bigley lived in a wealthy Baghdad neighborhood of villas surrounded by walls and protected by metal gates and armed guards. Their upper-middle-class stucco home was relatively nondescript, its perimeter wall low.

On the morning the men were abducted "there was no guard where there should have been," Patty Hensley told CNN.

-- Bill Montgomery, Jeffrey Scott and Clint Williams in Atlanta, Larry Kaplow in Baghdad, The Associated Press and The Washington Post contributed to this article.