BAGHDAD, Iraq – A roadside bomb killed a British soldier in southern Iraq yesterday as a new video from kidnappers threatened to kill two German hostages if Germany fails to stop cooperating with the Iraqi government.

In a series of apparent sectarian killings, police found the bodies of 16 handcuffed and blindfolded young men around Baghdad, and gunmen shot dead the wife and two sons of a Sunni Arab cleric north of the capital.

Kidnappers threatened to kill Thomas Nitzschke and Rene Braeunlich if Germany does not close its embassy in Iraq, withdraw all the German companies from Iraq, and stop cooperating with the Iraqi government within three days.

The videotape aired on Al-Jazeera television showed Mr. Braeunlich speaking and clasping his hands in front of him as if begging. No audio was heard.

The two men were abducted last week in the northern industrial city of Beiji.

The video came a day after a 28-year-old freelancer for the Christian Science Monitor also held hostage, Jill Carroll, appeared veiled and weeping in footage on Al-Jazeera.

American officials said they have ruled out meeting the kidnappers’ demand to release all Iraqi women in detention.

“Everything is being done to work with those who might have influence, and there are an awful lot of people who are calling for her release,” Secretary of State Rice said yesterday.

More than 250 foreigners have been taken captive since the war started and at least 39 have been killed.

An international journalist advocacy group, Reporters Without Borders, said it would send representatives to the Middle East to promote a campaign in the Arab press for the release of Ms. Carroll, who was seized in Baghdad on January 7.

The father of a kidnapped Canadian Christian activist urged the release of his son and three colleagues.

“I appeal for the captives of my son and his three friends to release them unharmed,” Dalip Singh Sooden said on Al-Jazeera yesterday. His son, 32-year-old Harmeet Singh Sooden, was seized November 26 in Baghdad.

British Corporal Gordon Alexander Pritchard, 31, was killed yesterday as he led a three-vehicle convoy hit by a roadside bomb in Umm Qasr, near the border with Kuwait.

He was the second British soldier killed in Iraq in as many days, making his death the 100th British military fatality since the conflict began in March 2003.

The 8,000-strong British contingent is based in the Shiite south, which is less violent than the Sunni Arab areas to the north where most of the 136,000 American troops operate.

Two children died during a clash between American troops and insurgents in the western town of Hit, an American Marine spokesman, Captain Jeffrey Pool, said.

Two other Iraqis were shot and killed when they violated orders for residents to stay in their homes during raids by paramilitary troops backed by American forces in Samarra, 60 miles north of Baghdad, police said.

Three Iraqi soldiers were killed and six wounded in a gunbattle in a tense Sunni Arab town 30 miles northeast of Baghdad, Buhriz.

In the volatile western Baghdad neighborhood of Ghazaliyah, 11 bodies were discovered in a truck, all shot in the head, police added. Five men’s bodies were also found near a sewage plant in the eastern Rustamiyah district where sectarian death squads often leave corpses. It was not known if they were Sunni Arabs or Shiites.

Sunni Arab and Shiites extremists have been carrying out reprisal killings that have claimed hundreds of lives and sharpened sectarian tensions as Iraqi politicians try to form a new government after December 15 national elections.The killings come at a time when American officials are pushing the Iraqis to include more Sunni Arabs, who form the backbone of the insurgency.

In what appeared to be a continuation of the killings, gunmen shot dead the wife and two sons of a Sunni Arab cleric, Qassim Daham al-Hamdani, Monday night in Muqdadiyah, about 60 miles north of Baghdad, police said. The cleric was not home.

Japan’s Kyodo News agency said Tokyo will begin withdrawing troops from Iraq in March and complete the pullout by May, ending its largest military mission since World War II. Japan’s Foreign Minister, Taro Aso, denied the report, saying no specific timetable had been discussed.

Kyodo said an agreement on the timetable had been reached during a secret meeting among officials from Australia, Britain, Japan, and America.

Iraq’s oil minister, Ibrahim Bahr al-Uloum, resigned yesterday for the second time within a month.