At least 50 people were killed and 140 wounded on Saturday in a series of car bombings that rocked Baghdad, Al Jazeera reported citing security officials, dpa reported.
The bombings targeted districts in the Iraqi capital that are mainly inhabited by Shiites, the officials said.
Iraq has been gripped by political and sectarian tensions, with Sunnis staging frequent protests in the past six months against the Shiite-led government of Prime Minister Nuri al-Maliki.
The protesters are seeking a repeal of laws they claim are being used against them.
The United Nations said this month that 1,057 people were killed in July, the deadliest month in more than five years.