Blasts heard in Baghdad this morning were caused by US artillery in military action against suspected insurgents.
Christopher Garver, a US military spokesman, told the Reuters news agency that US artillery was responsible for the explosions which shook the southern parts of the capital, but he refused to name any targets.
In addition, the US military says it has detained over 70 suspected insurgents and seized bomb making equipment in overnight raids.
Al-Qaida militants are said to have gathered in the outskirts of Baghdad to launch further attacks which have escalated since the US-led security crackdown in the capital.
Yesterday a car bomb attack killed over 55 people and injured a further 70 in the city of Karbala, one of the holiest Shia Islam areas in Iraq.
A bomb went off when people were walking in the streets on their way to prayers, close to the Imam Abbas shrine.
One witness told the New York Times: "I saw a woman who was in a jewellery store when the bomb exploded.
"I saw her running, and she was on fire. Some people tried to put her out with a blanket, but she was dead."
Nine US military deaths were also announced yesterday, including three American soldiers and two marines killed in Anbar province.
During Saturday morning two roadside bomb attacks in Baghdad claimed the lives of a further four US soldiers and wounded three more.
In addition the Shia cleric Moqtada al-Sadr sent a statement to the Iraqi parliament demanding that George Bush pulls US troops out of Iraq, noting that Democrats in the US are supporting a withdrawal date.
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