At least 16 people were killed and dozens others wounded on Monday in twin bomb explosions in downtown Baghdad, officials said.The attack took place in the morning when a suicide bomber detonated his explosive vest at a crowded site near al-Tayaran Square where many construction workers usually gather waiting for potential employers, Xinhua quoted reported. The second bomb exploded on a roadside. Earlier, the source put the casualties at six deaths and 24 wounded."The latest update is that the death toll rose to 16 people and 67 others were wounded in the double explosions in downtown Baghdad," an interior ministry official said.No group claimed responsibility for the attacks, but the Islamic State (IS) militant group, in most cases, is blamed for deadly attacks targeting crowded areas in Iraq, including markets, cafes and mosques.Last week, a suicide bombing in Baghdad killed eight and wounded at least 10 others when the blast struck a northern Baghdad neighbourhood targeting a police checkpoint on a busy street.