A car bomb and several mortars in central Baghdad have killed at least 25 people and injured 45 others.

The car bomb, in the shopping district of Karrada, heavily damaged a building, raising fears the death toll could rise. The mortars landed nearby.

Although there have been bombings in Karrada before, the mostly Shia area is one of the few relatively stable districts of the capital.

US and Iraqi forces have been focusing their efforts on stabilising Baghdad.

The US military may boost its force in Iraq by delaying the scheduled departure of some troops involved in routine rotations.

One defence official, speaking on condition of anonymity, said the idea would be to create 'a momentary overlap' of at least a brigade, or roughly 3,500 troops.