Two American soldiers and seven employees of a U.S. contractor in Iraq might be in enemy hands, Lt. Gen. Ricardo Sanchez said Monday in a news briefing from Baghdad.

Also Monday, Qatar-based Al-Jazeera reported that a Russian energy company said 11 of its employees were kidnapped in Iraq during a clash in Baghdad that killed two Iraqi security guards. No other details were immediately available.

With the missing Americans, eight of the nine are "unaccounted for," and Thomas Hamill (search), the Macon, Miss., truck driver kidnapped on Friday, is known to be a hostage. Hamill was snatched by gunmen who attacked the fuel convoy he was guarding.

"He's a great guy," Scott Boyd, a Hamill family friend and reporter/publisher of the local newspaper The Beacon, told Fox News Monday. "Tommy will do whatever he can to keep his spirits high."

Boyd said the normally divided town of Macon is rallying around the Hamill family.

In the last week, more than 40 foreigners from 13 countries have been kidnapped in Iraq by insurgents.

The United Nations on Monday urged the immediate release of kidnapped aid workers in Iraq and called for humanitarian organizations to be given access to Iraqis in distress, especially those who need medical attention.

"Humanitarian access to affected civilians, and access of those civilians in need to basic supplies and services are of major concern," Ross Mountain, the acting U.N. special representative for Iraq, said in a statement issued from the U.N. office in Amman, Jordan.

"Aid workers, NGOs and other humanitarian organizations must be able to safely reach populations in distress, including those who require urgent medical assistance," he said.

U.S. Secretary-General Kofi Annan appealed Saturday to all parties "to exercise restraint in order to minimize danger to innocent civilians."

Hamill, 43, is one of seven missing employees of the Houston-based engineering and construction company Kellogg, Brown & Root — a division of Halliburton (search), the firm that Vice President Dick Cheney ran during the 1990s. Two U.S. soldiers are also unaccounted for.

The whereabouts of all nine became unknown after Friday's attack on the fuel convoy.

The military has been trying to regain control of supply routes after several convoys were ambushed and at least 10 truck drivers were kidnapped. Nine of various nationalities — including Turks and Pakistanis were released, but Hamill remains a captive.

Hamill's captors threatened to kill him by Sunday morning unless U.S. troops ended their assault on the city of Fallujah. The deadline passed with no word on Hamill's fate.

Halliburton ran a statement on its Web site about the kidnappings.

"We at Halliburton and KBR remain anxious but prayerful that our colleague, Thomas Hamill, will be returned safely. In these agonizing moments, the company is doing everything possible to assist the family. ... Our thoughts remain with our six other missing colleagues ... and we remain hopeful for our other co-workers' safe return," the statement reads in part.

KBR has a long history of working for the U.S. government. Previous government contracts included building the Phan Rang Air Base in Vietnam in 1965 and producing Navy ships during World War II.

More than 24,000 KBR employees and subcontractors are working in the Kuwait-Iraq region, said Wendy Hall, a Halliburton spokeswoman. Their duties include extinguishing oil well fires and cleaning oil sites.

"Our work is difficult and in a dangerous environment and we are angered and deeply saddened by this situation," Halliburton said in a statement. "Halliburton and its subcontractors have lost about 30 personnel while performing services under our contracts in the Kuwait-Iraqi region."

The company declined to identify the six missing workers or discuss details of the attack in order to protect their privacy, Hall said.

Two men who drove trucks for Halliburton until this weekend, Stacy Clark and Stephen Herring, said it was becoming too dangerous in Iraq, according to their wives.

Donna Clark and Chrissy Herring, who were to meet their husbands at Bush Intercontinental Airport in Houston on Monday, said both men were in convoys that were ambushed last week.

Donna Clark, 31, said her husband was "in a panic" when told her he was coming home. Both men said there was not enough protection in the convoys, the wives said.

Halliburton offered drivers and other workers $80,000 tax-free for working in Iraq for a year, or up to $120,000 with overtime. However, workers are allowed to return home without questions.

Halliburton has earned as much as $6 billion in contracts from the U.S. invasion of Iraq, but the company has been under fire for allegedly overcharging the government. Halliburton denies wrongdoing and says the company is a political target.

Meanwhile, Al-Jazeera television said 11 Russians working for a Russian energy company were kidnapped during a clash in Baghdad. The station did not say when the reported abduction took place.

Gunmen battered American supply lines around Baghdad on Monday, attacking a convoy of flatbed trucks carrying M113 armored personnel carriers south of the capital and setting them ablaze. A supply truck was burned and looted on the road from the airport.

Also, two Czech Television journalists on assignment in Iraq are missing and believed kidnapped, a spokesman for the station said Monday.

The station lost all contact with reporter Martin Kubal and cameraman Petr Klima on Monday morning, and unconfirmed reports indicated they were abducted while traveling from Baghdad to Amman, Jordan, said spokesman Martin Krafl.

The station was informed of the kidnapping by a taxi company whose driver was taking them to Amman, Krafl said, adding that the broadcaster has asked the Czech Foreign Ministry for assistance.

A third reporter, Vit Pohanka of Czech Radio, has been missing since Sunday, according to the head of the radio station's foreign desk, Jiri Hosek. Pohanka might have been traveling to Amman with the other two reporters, according to unconfirmed reports, Hosek said.

And seven Chinese civilians abducted by insurgents in central Iraq Sunday evening were released Monday, after Beijing urged Iraq's leaders to help free the hostages.

Other insurgents promised to release three Japanese by Sunday, but the Japanese Embassy in Baghdad said Monday that they had not been freed.

Fox News' Bret Baier, Mike Emanuel, Ian McCaleb, Catherine Donaldson-Evans and The Associated Press contributed to this report.