At least 72 people have been killed in bomb attacks targeting Shia Muslims in southern Iraq and the capital Baghdad.
Officials said 45 pilgrims died in a suicide attack in Nasiriya and 27 people died in Shia areas of Baghdad.
The attacks were the deadliest since the last US soldiers pulled out of Iraq on 18 December.
Sectarian tensions have risen since the US pullout and since an arrest warrant was issued for Sunni Vice-President Tariq al-Hashemi.
The BBC’s Rafid Jabboori in Baghdad says Iraq is going through a severe political crisis and the situation in the country is tense.
Regional health chief Hadi Badr al-Riyahi said hospitals in Nasiriya had received 45 killed and 68 wounded.
Recent attacks in Iraq
- 5 January – At least 27 die in blasts in two Shia areas of Baghdad. A roadside bomb kills 45 pilgrims near Nasiriya
- 4 January – At least three die in bombings and grenade attacks in Baquba and Abu Ghraib, north of Baghdad
- 26 December – At least seven killed in suicide car bomb attack outside Iraq’s interior ministry
- 22 December – 68 killed in multiple blasts in Baghdad
- 5 December – At least 30 killed in attacks targeting Shia pilgrims in central Iraq
- 27 October – 38 killed, 78 injured in twin bomb blasts in a Shia area of Baghdad
- 12 October – 28 killed by car bombs and roadside bombs around Baghdad
- 15 August – At least 60 killed in co-ordinated attacks in several Iraqi cities
A provincial government website said pilgrims had been walking towards the holy city of Karbala when a suicide bomber detonated an explosives belt at a rest stop. The blast happened in the run-up to Arbaeen, a Shia holy day.
The Baghdad attacks targeted civilians in the Sadr City and Kadhimiya areas, the Interior Ministry said. At least 70 people were wounded.
The first two explosions struck Sadr City, killing at least 12 people. The first bomb was on a motorbike which exploded near where labourers were gathering to look for work.
“There was a group of day labourers gathered, waiting to be hired for work. Someone brought his small motorcycle and parked it nearby. A few minutes later it blew up, killed some people, wounded others and burned some cars,” a police officer told Reuters at the scene of the attack.
Some 30 minutes later a roadside bomb exploded near a tea shop.
Less than two hours after that blast, two car bombs exploded simultaneously in the Kadhimiya district killing 15 people, officials said.
Iraqi military spokesman Maj Gen Qassim al-Moussawi said the aim of the attacks was “to create sedition among the Iraqi people”.
He said it was too early to say who was behind the bombings.
The attacks were condemned by the US.
US State Department spokeswoman Victoria Nuland described them as “desperate attempts by the same kind of folk who have been active in Iraq trying to turn back the clock”.
Iraq’s power-sharing government has been in crisis since an arrest warrant was issued for Sunni Vice-President Tariq al-Hashemi on terrorism charges two weeks ago. He has denied the accusations against him.
The al-Iraqiyya group, the main Sunni bloc in parliament, is boycotting the assembly in protest. It accuses Prime Minister Nouri Maliki, a Shia, of monopolising power.
Mr Hashemi is currently in Irbil in Iraqi Kurdistan, under the protection of the regional government. Mr Maliki has demanded that they give him up.
However, Kurdistan Regional President Masoud Barzani recently told BBC Persian that they had not received a request to extradite Mr Hashemi, only a letter to say he is forbidden from leaving the country.
Mr Barzani said “distrust” of Baghdad’s judicial system was hampering efforts to resolve the crisis.
Labourer Ahmed Khalaf, speaking to AFP at the site of one of the Sadr City explosions on Thursday, said: “Political leaders fight each other for power, and we pay the price.
“How is it our fault if al-Hashemi is wanted, or someone else is wanted?” he asked. “Why should we pay instead of them?”