Twenty-two people were killed in attacks in Baghdad, an interior ministry official said.

And four people were killed in Salaheddin, a police colonel in the province said, while six more were killed in Diyala, police in that province said.

Both provinces lie north of the capital. Diyala is a confessionally mixed province that has long been one of Iraq's most restive. Salaheddin province has as its capital the city of Tikrit.