A suicide car bomb exploded late-morning outside a police intelligence office in Baquba north of the Iraqi capital, killing a man and wounding 15 other people, a security official and a doctor said.
The bombing targeted the office, located in a central market, at about 11:00 am (0800 GMT), the security official said, adding that guards protecting the building and girls on a nearby school bus were among the wounded.
Just before the suicide bomber blew up the car, insurgents threw several hand grenades into the intelligence office. It was the first attack against the centre, which was opened three years ago.
Dr Firas al-Dulaimi, who works at the main hospital in Baquba, said the wounded included 10 girls, two men, and three guards from the intelligence office, who suffered serious injuries.
In central Baghdad, gunmen early on Monday broke into the home of a Christian woman, Rafah Toma, shot her dead and made off with a number of her possessions, an interior ministry official said.
Toma, who lived alone in Al-Wahda neighbourhood, is the latest victim of a string of attacks on Christians in Iraq, with the official saying she was likely targeted because of her religion.
On Thursday, at least two Christians were killed and 16 others wounded in a wave of bomb attacks on Christian targets in Baghdad, while 44 worshippers, two priests and seven security forces members were killed in an October 31 attack by militants on a Baghdad church.
The interior ministry official, who would not be named, also said that a policeman was shot dead by gunmen with silenced weapons in Taifiya in northern Baghdad. He gave no further details.
The policeman's death followed a string of similar attacks on Sunday night in which a traffic police colonel, two other police, an army captain and an engineer were gunned down in five separate attacks in Baghdad by gunmen with silenced weapons. Gunmen also severely wounded a colonel with the interior ministry on Sunday.
The US military on Monday announced that two US soldiers have been killed in central Iraq. "Two US service members were killed in central Iraq Sunday night while in support of Operation New Dawn," a statement from the US military said.
Operation New Dawn is the name for US military activities in Iraq from September 1, 2010, after the declared end of combat operations. "This was one incident resulting in the death of two US service members. These are the first deaths of any US service member in 2011," a spokeswoman for the military said, without giving further details on how the two were killed, or to which branch of the military they belonged.
The latest deaths brings to 4,432 the number of American soldiers to have died in Iraq since the 2003 US-led invasion to oust Saddam Hussein, according to an AFP tally based on data from independent website www.icasualties.org.
According to the website, 60 members of the US military were killed in Iraq in 2010 -- by far the smallest number since 2003.
Some 50,000 US troops remain in the country, but a security accord between Baghdad and Washington requires that they be withdrawn by the end of 2011.