At least 75 people are reported to have been killed in a massive explosion in Baghdad.
A bomb went off near the Shi’ite Khilani mosque in the centre of the city.
The blast came during a relatively calm period in the Iraqi capital, after a four day curfew was imposed last week.
Dozens of injured people have been taken to hospital.
The attack comes as the US military deploys 10,000 soldiers, backed up by helicopters, in an offensive against Al-Qaeda, north of the capital.
The army says 22 militants have been killed in the early stages of the offensive around the city of Barquba in the Diyala province.
The operation coincides with smaller crackdowns against militants in recent days around Baghdad.
An unknown number of militants have been taken into custody.
The US military says it has now completed its troop build-up in Iraq to 160,000 soldiers.