BAGHDAD, Iraq - The military announced that two American soldiers died in separate clashes Wednesday.

One soldier died from injuries after a clash in northern Mosul. The soldier was among several people injured after soldiers tried to conduct a routine check of a taxi, Lt. Col. Andre Lance said. The taxi's passengers opened fire on the soldiers, and they shot back, killing the assailants and causing the taxi to explode. Officials believe it was carrying explosives.

Another soldier was killed when his patrol came under fire in Baghdad, the military said. The gunmen disappeared into a nearby crowd, but five suspects were later detained.

Also, early today, a suicide bomber blew up his car south of Kirkuk, killing two Iraqi Army soldiers and three bystanders, and a second car bomber attacked a joint U.S.-Iraqi patrol in the center of Samarra, killing three people and injuring more than a dozen.

The explosion in Tuz Khormato injured at least 16 people, including eight soldiers, said Sarhad Qader, a police official. The blast occurred near an Iraqi Army checkpoint guarding a Shiite shrine where pilgrims had gathered to celebrate a major religious festival.

In Samarra, north of Baghdad, another suicide car bomber attacked a joint U.S.-Iraqi patrol in the city center, said police official Qassim Omar. Dr. Alaa Al-Deen Mohammed of the city hospital said at least 15 people were injured.

Across the country, Shiite Muslims observed a religious holiday marking the end of a 40-day mourning period for one of Shiites' most important saints, the grandson of Prophet Muhammad, Imam Hussein, who was killed in a seventh century battle.

Officials have been on the alert for attacks targeting Shiite Muslims during the festival, which draws people to shrines across Iraq. The biggest gathering is in Karbala, where hundreds of thousands of Shiite pilgrims visited two holy shrines today.

On Wednesday, gunmen fired on pilgrims in southern Iraq, killing one person. Two days earlier, two separate attacks on pilgrims left four dead.

Al-Jazeera satellite television aired a tape Wednesday showing three kidnapped Romanian journalists and a fourth unidentified person - possibly an American - with guns pointed at them. The station said the four were being held by an unidentified group and no demands were made.