At least 75 people were killed and another 190 wounded after a truck bomb exploded next to a Shia mosque in central Baghdad on Tuesday, the BBC reported.

The bomb went off in a busy shopping district next to the al-Khilani mosque just across the river from the heavily guarded "green zone" in the Iraqi capital, which hosts the government buildings.

The blast is the latest in a series of bombings targeting mosques, both Shia and Sunni. Last week, following an attack on the al-Askari shrine in Samarra, a Shia holy site, which sparked a wave of revenge bombings of Sunni mosques.

Tuesday's blast came at a particularly busy part of the day and destroyed the mosque's prayer hall, rocking the city centre.

It came just as 10 000 US troops began an assault on Sunni insurgents linked to the al-Qaeda north of Baghdad.