Updated

An Al Qaeda (search) linked group threatened in a videotape Saturday to behead two blindfolded Americans and a Briton within two days, and insurgents carried out a new string of car bombings, killing at least 19 Iraqis and two American soldiers.

The video was the first word on the fate of Americans Jack Hensley and Eugene Armstrong and Briton Kenneth Bigley since the three construction workers were kidnapped from their Baghdad home two days earlier.

"My job consists of installing and furnishing camps at Taji (search) base," each man said in turn after identifying himself, as all three sat on the floor, blindfolded, slightly bowed but apparently unharmed. At one point, a militant's rifle pointed down at the head of the man who identified himself as Hensley.

The Tawhid and Jihad group, led by Jordanian militant Abu Musab al-Zarqawi (search), claimed responsibility for the abduction and demanded the release of Iraqi women detained in two American facilities.

The footage surfaced as a new hostage-taking was revealed. Another group claimed it had kidnapped 10 workers for an American-Turkish company and threatened to kill them in three days if their firm didn't leave Iraq.

Kidnappings and spectacular bombings have become the signature weapons of insurgents waging a 17-month campaign against U.S. and Iraqi forces, a campaign that has persisted since the interim government of Prime Minister Ayad Allawi took power in June. Some 300 people have been killed in violence the past week.

Nevertheless, Allawi insisted U.S. and Iraqi forces were winning the fight and said progress would be made to calm the violence before crucial elections set for January.

The insurgency is "not getting stronger; it's getting more desperate. We are squeezing out the insurgency," Allawi said, speaking in an interview due to be aired Sunday on ABC's "This Week."

"We are winning. We will continue to win. And we are going to prevail," he said.

Guerrillas have struck with increasing sophistication in Baghdad, the center of Allawi's authority, and have dealt punishing blows against Iraq's security forces — which are the lynchpin of the U.S.-Iraqi strategy for fighting the insurgency.

On the road to Baghdad's airport Saturday, insurgents set off a car bomb near an overpass as a U.S. convoy passed, wounding three U.S. soldiers. When other American troops moved to the scene, another car bomb exploded, killing two soldiers and wounding eight more.

In the northern city of Kirkuk, a car sped at a crowd of would-be recruits lined up at the offices of the Iraqi National Guard. Guardsmen opened fire on the vehicle and it exploded, leaving the street strewn with bloodied bodies, twisted metal and shards of glass.

At least 19 people were killed and 67 wounded, the Health Ministry said.

It was the third bombing this week targeting the beleaguered security forces, seen as collaborators with the United States and its allies.

The attack occurred as recruits lined up to read the lists of those who had passed the physical fitness test, said Rustem Abdellah, one of the job-seekers who suffered burns to his face and chest.

"I am a graduate from the oil institute," Abdellah, 33, said from his hospital bed. "But there are no jobs available in the oil sector, and I was forced to join the guard force because of the difficult economic situation."

The videotape showing the American and British hostages was aired in part on Al-Jazeera television, then posted in full on a Web site known for carrying Islamic militant material.

In the footage, a masked militant dressed in black stood behind the men and read from a statement, saying the three were kidnapped because they offer logistic support to American troops. He threatened to kill them unless Iraqi women detained at the American-controlled Abu Ghraib and Umm Qasr prisons are freed within 48 hours.

A U.S. military official said two Iraqi women were in U.S. custody.

The militant accused Allawi of enabling "infidel foreigners" to "violate the honor of Muslim women, humiliate people and suck up the riches of the country" and gave the United States and Britain 48 hours to release Iraqi women detained at .

If the demand is not met, the speaker warned: "By the name of God, these three hostages will get nothing from us except their throats slit and necks chopped, so they will serve as an example."

In Armstrong's home town of Hillsdale, Mich., his brother, Frank Armstrong, said he'd spoken with the FBI about the abduction but declined to comment further.

"We only know what they're showing on television," said Minnta Davis, Armstrong's cousin. "We just know there are just a lot of prayers for him."

Both the prison facilities named in the video are run by American forces. Umm Qasr is in British-controlled southern Iraq, and Abu Ghraib is a prison near Baghdad where U.S. soldiers were photographed sexually humiliating male prisoners. Fears about the safety of women inmates have multiplied since then.

Lt. Col. Barry Johnson, a U.S. military spokesman in Baghdad, said coalition forces do not hold any women at Abu Ghraib or at Camp Bucca, a U.S. detention facility near Umm Qasr.

"The only females we hold are two high-value detainees, which are kept with the other approximately 100 high-value detainees in a separate, secure location," Johnson said.

He did not rule out the possibility that women were among an estimated 1,500 prisoners at an Iraqi facility for convicted criminals at Umm Qasr.

Justice Ministry official Nouri Abdul Raheem said a U.S.-Iraqi committee reviewing the cases of detainees had decided to release all women and juveniles within the next two weeks.

Gulf Supplies and Commercial Services, the kidnapped men's employer, refused to comment on the tape when contacted by The Associated Press.

Meanwhile, a previously unknown group calling itself the "Salafist Brigades of Abu Bakr Al-Siddiq" claimed it was holding 10 hostages working for an American-Turkish company, according to a tape broadcast by Al-Jazeera on Saturday. The group said the company had to leave Iraq within three days or the hostages would be killed.

The hostages' nationalities nor the name of their company were not given. The authenticity of the tape could not be immediately verified.

More than 100 foreigners have been kidnapped in Iraq, and many have been executed. At least five other Westerners are currently being held hostage here, including an Iraqi-American man, two female Italian aid workers and two French reporters.

In other developments:

—Hospital officials said residents had found the body of Anbar province's deputy governor, Bassem Mohammed, who was kidnapped earlier this month.

—British troops pulled out of the main office of radical Shiite cleric Muqtada al-Sadr in the southern city of Basra after occupying it and seizing a weapons cache there a day earlier amid fighting that killed three and wounded five.

—Iraqi Airways resumed regular international flights for the first time since 1990 U.N. sanctions, with a plane taking off from neighboring Jordan and another landing in the Syrian capital.

—U.S. forces clashed with gunmen in the insurgent stronghold of Ramadi after launching an offensive to destroy a suspected militant cell linked to al-Zarqawi, the military said. There was no immediate word on casualties.

—A roadside bomb exploded in a small side street in central Baghdad, killing one Iraqi man and seriously wounding two, police and witnesses said.