Baghdad - Seven children were killed and 42 people were injured in a bomb explosion, which caused a hole as deep as 2 feet by 5 feet wide, outside a school in a Shiite district in Baghdad, Monday, police said.
The explosion occurred in the slums of Sadr City in Baghdad, when the children of primary school between the ages of 6 and 12 years was home from school, said a military officer.
Not yet clear whether the bomb accidentally detonated at that moment or whether accidentally exploded after a pile of burning rubbish, the official said.
The blast shattered windows and scattered school books in the classroom that are stained with blood.
The bomb exploded at a building complex that includes elementary and school for children between the ages of 13 and 15 years, officials said.
Violence in Iraq declined dramatically in 18 months. The number of civilian deaths last month reached 88, the lowest since the 2003 invasion, according to government data.
A bomb in Sadr City, a poor area which is considered as the headquarters of the Shia militant, killing 72 people and injured another 127 in June.
Earlier Monday, a number of unidentified armed men shot dead five people in the Sunni areas that maintain a checkpoint on the northern outskirts of Baghdad, police said. The guards are part of the Sahwa, the militia that once the U.S. ally and now a pro-Iraqi government.
The day before, Sunday, a number of assailants shot dead four policemen assigned to guard the security of the traders in a vegetable market on the outskirts of Baghdad.
The attacks on that day also occurred in the oil city of Kirkuk, northern Iraq, killing a soldier, a private security guard and a member of the Sahwa militia.
Series of attacks and bombings since the U.S. troops be withdrawn from the cities of Iraq by the end of June had raised questions about the ability of Iraqi security forces to protect the population from guerrilla attacks as the Sunni militant group al-Qaeda.
Bombings in Baghdad and near the troubled city of Mosul, apparently aimed at stirring more deadly sectarian violence between the Sunni and Shia people that brought Iraq to the brink of civil war.
Although there was a decrease in overall levels of violence, attacks on security forces and civilians are still going on in Kirkuk, Mosul and Baghdad.
Many Iraqis are also worried about the attacks against the Shia will be lit again deadly sectarian violence between Sunni and Shia the new subsided in 18 months. Tens of thousands of people died in violence since the US-led invasion of Iraq in 2003.
The death toll from violence in Iraq has fallen to one-third to 275 in July, the first month of Iraqi forces responsible for security in urban areas since the US-led invasion in 2003.
Violence declined significantly in Iraq in recent months, but increased attacks ahead of a U.S. military withdrawal, and 437 people have died in Iraq in June - the highest number of deaths within 11 months.
Prime Minister Nuri al-Maliki warned in June that the guerrillas and the militias might increase their attacks in an effort to undermine public confidence in Iraqi security forces.