Last night's attack was the first since al-Qaida-linked militants last week threatened a wave of violence against Christians in Iraq. The community went so far as to tone down its Christmas celebrations in what was a peaceful holiday, but the latest attack demonstrated the intent of militants to keep up their deadly pressure on Christians.
Assailants in southwestern Baghdad threw two grenades inside the home of a Christian family, killing two people and injuring five more, police said. In a different neighbourhood in eastern Baghdad, militants planted a bomb near a Christian home. Two people were injured in that attack.
Then another bomb planted near a Christian house in western Baghdad exploded, wounding one member of the family as well as a civilian who was driving by, police said.
Iraqi military spokesman Maj Gen Qassim al-Moussawi confirmed that two people were killed. He said a bomb planted near the fence of a Christian home in southern Baghdad also exploded but he had no information about casualties in that incident.
"The aim of these attacks is to prevent Christians from celebrating the New Year's holiday," al-Moussawi said.
There was no immediate claim of responsibility, but such attacks have generally been the work of Sunni militants linked to al-Qaida.
The casualties were confirmed by hospital officials. All officials spoke on condition of anonymity because they were not allowed to talk to reporters.
The attacks are sure to ratchet up tension in the tiny Christian community still living in Baghdad. At least 68 people were killed in October when militants stormed a Baghdad church during Mass and took the congregation hostage.
Thousands of Iraqi Christians have fled to northern Iraq, fearing further attacks.