A series of bomb attacks across Iraq have killed 31 people and wounded well over 100 others, Belfast Telegraph said.

The attacks, many involving car bombs, took place less than a week before Iraqis in much of the country are scheduled to vote in the first elections since the 2011 US troop withdrawal. The vote will be a key test of security forces' ability to keep voters safe.

There was no immediate claim of responsibility, but co-ordinated attacks are a favourite tactic of al-Qaida's Iraq branch.

Iraqi officials believe the insurgent group is growing stronger and increasingly co-ordinating with allies fighting to topple Syrian president Bashar Assad across the border.

They say rising lawlessness on the Syria-Iraq frontier and cross-border co-operation with the Syrian militant group Nusra Front has improved the militants' supply of weapons and foreign fighters.

Nearly all of the deadly attacks reported by police officials were bombings, which struck Baghdad, the western city of Fallujah, the contested northern city of Kirkuk and towns south of the capital.