Four of the soldiers were killed on Thursday by a roadside bomb in Samarra.
"The attack targeted a military convoy in central Samarra. Four soldiers were killed and four wounded," a lieutenant colonel, Mahmud Muhammed, said.
Elsewhere, several British soldiers and Iraqi civilians were wounded in an explosion outside a British military base near the southern Iraqi city of Basra, the military said.
"An explosion occurred near to one of the entrances to the base. Several Iraqi civilians and United Kingdom military personnel have suffered injuries," the British military said in a statement.
"They are currently being assessed and treated at the British military hospital inside the base," adding that further details would be forthcoming.
The ministry of defence in London confirmed Thursday's incident. A witness said the explosion was caused by a car bomb but there was no independent confirmation.
A British base came under attack
in Basra in the south on Thursday
The witness said a car careered towards the main gate of the base in Shaibah, when two British military vehicles tried to prevent it from entering and the car blew up.
"This was the time when many Iraqis working on the base were leaving and several were injured," the witness added.
Also on Thursday, an Iraqi soldier was killed and another wounded in a mortar attack on a military position in Siniya, west of the troubled town of Baiji, Captain Ali Yusuf said.
The British security worker, along with an Iraqi colleague, was killed in an ambush near the Baiji power station complex, which they were helping to protect, Major Neal O'Brien, a spokesman for US forces based in Tikrit, said.
On Thursday, a US military spokesman identified the foreigner missing from that attack as a Brazilian citizen. The British security contractor and the Iraqi, who were not identified, worked for the London-based Janusian Security Risk Management Ltd.
Car bombings are taking a steady
toll on Iraqi troops and policemen
"We are proud of their professionalism and dedication and of the role they played in trying to help in the reconstruction of that country," David Claridge, managing director of the firm, said.
"We are investigating the matter and are working with the local authorities in their efforts to locate the missing civilian."
Another foreigner was reportedly seized in the same area after armed men stopped his car and killed two Iraqi police officers accompanying him, Iraqi police said.
Iraqi police had identified him as a Japanese engineer who also worked for a power station in Baiji.
But officials in Tokyo and at the Japanese embassy in Baghdad said they had not confirmed the report, adding that some information indicated the victim was not Japanese.
It was not clear whether the two attacks were connected.
Weeks after the Falluja assault,
violence continues to stalk Iraq
Separately, Aljazeera has learned that a number of Iraqi and US soldiers were injured in clashes between them and anti-interim government fighters in al-Maqdadiya area, northeast of Baquba, on Wednesday night.
One Iraqi and two US vehicles were damaged in the skirmish.
On the fighters' side, a leader of the Jihad in the Land of Two Rivers' movement was killed.
Aljazeera also reported that US forces have taken over al-Salam hospital in the northern Iraqi city of Mosul to use as a military base.
But a US military official denied such a takeover, saying Iraqi soldiers guarding the building had merely fended off an attack. "The US did not take control of the hospital," Central Command spokesman Eric Clark said on Thursday.
The seven-storey building is Mosul's largest hospital.