BAGHDAD - At least 16 people were killed and 67 others were wounded Monday in twin bomb explosions in downtown Baghdad, an interior ministry source said.

"The latest update is that the death toll rose to 16 people and 67 others were wounded in the double explosions in downtown Baghdad," the source told Xinhua on condition of anonymity.

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, the source said.

The other blast involved a roadside bomb, which went off at the scene, the source added.

Earlier, the source put the casualties at six deaths and 24 wounded, citing police reports.

No group has so far claimed responsibility for the attacks, but the Islamic State (IS) militant group, in most cases, is responsible for deadly attacks targeting crowded areas in Iraq, including markets, cafes and mosques.