The coordinated attacks targeting Shi’ites bore the hallmarks of Sunni insurgents linked to al-Qaida, although there was no immediate claim of responsibility.
The bombings began early in the morning when explosions struck two Shi’ite neighbourhoods in Baghdad, killing at least 27 people.
A few hours later, a suicide attack hit Shi’ite pilgrims heading to the holy Shiite city of Karbala, killing 45, said provincial official Quosay al-Abadi.
The explosions took place near Nasiriyah, about 320km southeast of Baghdad.
The blasts occurred in the run-up to Arbaeen, a Shi’ite holy day which marks the end of 40 days of mourning that follow the anniversary of the death of Imam Hussein, a revered Shi’ite figure. During this time, Shi’ite pilgrims from across Iraq make their way to Karbala, south of Baghdad.
Baghdad military spokesman Major General Qassim al-Moussawi said the aim of the attacks is “to create turmoil among the Iraqi people.” He said it was too early to say who was behind the bombings.
The attacks began in Baghdad with the explosion of a bomb attached to a motorcycle near a bus stop where day labourers gather to look for work in the Shi’ite Sadr City neighbourhood.
That attack was followed by the explosion of a roadside bomb. Police found a third bomb nearby and defused it.
The two Sadr City blasts killed 12 people, according to police and medical officials.
Less than two hours later, two explosions rocked the Shi’ite neighbourhood of Kazimiyah in the north of the capital, killing 15 people.
Hospital officials confirmed the causalities from the four blasts, which included more than 60 wounded.
The attacks were the deadliest in Baghdad since December 22, when a series of blasts killed 69 people in mostly Shi’ite neighbourhoods. An al-Qaida front group in Iraq claimed responsibility for those attacks.
The new violence will only exacerbate the country’s political crisis, pitting politicians from the Shi’ite majority who dominate the government against the Sunni minority, which reigned supreme under the dictatorship of Saddam Hussein.
Fears have already been running high that sectarian tensions could re-ignite Shi’ite-Sunni warfare, that just a few years ago, pushed Iraq to the brink of civil war.