BAGHDAD: At least 10 people were killed and 29 wounded Friday in bomb blasts that struck two districts of Baghdad, police and hospital sources said.

The deadliest was a car bomb in the northern Shia neighbourhood of Sadr City, which has been frequently targeted and where security is usually heightened ahead of Friday prayers.

At least seven people were killed and 21 wounded in the explosion that rocked one of the large neighbourhood's main streets, a police colonel and hospital sources said.

Three roadside bombs also went off almost simultaneously near a Shia mosque close to the central Kholani square, killing three people and wounding eight, two police officers said.

Jihadist group the Islamic State seized large parts of Iraq's west and north in June, before stopping its offensive a few dozen kilometres from Baghdad.

But it has continued to wreak havoc in the capital, mainly with suicide attacks, car bombs and improvised explosive devices targeting security forces.