'Our latest reports put the toll at 63 killed and 185 wounded in a series of bomb attacks in Baghdad,' Xinhua reported the source as saying on condition of anonymity.
Four car bombs ripped through Baghdad in addition to 10 roadside bombs and a rocket barrage that struck the city during the morning rush hour.
The attacks struck the districts of Alawi, Karradah, Bab al- Muadham in central Baghdad, Shaab, Shulla, Adhamiyah in the north, Baiyaa, Amil, Amin, Doura, Abu Dsheer in southern Baghdad, Yarmouk, Harthiyah and Ghazaliah in the west.
Thursday's incidents were a first major indication of escalation of violence in the country after US troops' withdrawal from the country. The last batch of US combat forces in Iraq crossed into neighbouring Kuwait on Sunday (Dec 18).
An Iraqi health ministry official earlier said that the attacks killed 57 people and wounded 176.
Iraqi security forces blocked many main roads in the capital and dozens of police and army vehicles were deployed across the city, as sounds of sirens of ambulances and fire engines could be heard across the capital.