A wave of bomb attacks and shootings in Baghdad and north of the capital has killed at least 107 people, say security and medical officials, according to BBC News.

Many of those killed were security forces - who appear to have been a prime target.

One of the worst-hit places was Taji, a Sunni neighbourhood some 20km (12 miles) north of Baghdad, where at least 41 people were killed.

At least 216 people were wounded on one of the bloodiest days of the year.

Some 13 Iraqi towns and cities were hit in the spate of apparently co-ordinated attacks.

Fatal bombings hit Shia districts in Baghdad. In the deadliest attack, a car bombing at a government building in Sadr city killed at least 16.

At least five car bombs hit the northern oil city of Kirkuk, and further north in the city of Mosul at least nine people died, reportedly including six soldiers.

Bombs and shootings in the restive province of Diyala killed 11.

Saadiya, Khan Beni-Saad, Tuz Khurmatu, Dibis, Samarra and Dujail were also said to have suffered attacks.

The attacks come days after a man purporting to be Abu Bakr al-Baghdadi, the leader of al-Qaeda in Iraq, declared a new offensive to retake areas the group retreated from before U.S. soldiers left the country last December.

Analysts suggest al-Qaeda is seeking to deepen the sectarian political crisis in Iraq that is setting Sunni Arab and Kurdish leaders against their Shia counterparts.

They say Monday July 23 violence seemed to aim at security forces and government offices - favourite targets of al-Qaeda.