Suicide bombers have attacked Shi'ite pilgrims in Baghdad and a primary school and police station in a Shi'ite village in north Iraq, killing at least 24 people, officials say.
Violence is at a level unseen since 2008, amid persistent fears of a relapse into the kind of intense Sunni-Shi'ite bloodshed that peaked in 2006-2007 and killed tens of thousands of people.
In the capital on Sunday, a suicide bomber detonated explosives near pilgrims who were walking to a shrine in the north of the city to commemorate the death of Imam Mohammed al-Jawad, the ninth Shi'ite imam.
The blast killed at least nine people and wounded at least 30, officials said.
A bus parked near the site of the explosion had a streak of blood running from a shattered window down its side.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Body parts hung from a roadside tree, and blood was spattered on a pavement and the underside of a bridge.
Two young boys sifted through debris at the site, where items including sandals and a policeman's belt buckle lay in a pool of water formed when emergency personnel hosed the street down.
Iraq is home to some of the holiest sites in Shi'ite Islam, and millions of pilgrims visit them each year.
But crowds of pilgrims are frequently targeted by Sunni militants including those linked to al-Qaeda, who consider Shi'ites to be apostates.
Two more suicide bombers on Sunday targeted the Turkmen Shi'ite village of Qabak in Nineveh province about 50km from the border with Syria.
The bombers detonated explosives-rigged vehicles at a police station and a primary school, killing 15 people and wounding 44, local official Abdulal Abbas told AFP.
The dead were 10 children and five police, Abbas said, adding that the school bombing collapsed the building's roof.
Sunday is a normal schoolday in Iraq, where the weekend is Friday and Saturday.
Sunday's blasts came a day after violence including an attack on Shi'ite pilgrims in Baghdad and a suicide bombing at a cafe killed at least 73 people.
Among them were two journalists from the Sharqiya television channel gunned down in the northern city of Mosul.
UN envoy Nickolay Mladenov called on Iraq's "political, religious and civil leaders to work together with the security forces" to curb the bloodshed.
"It is their responsibility to ensure that pilgrims can practise their religious duties, that schoolchildren can attend their classes, that journalists can exercise their professional duties, and that ordinary citizens can live a normal life," Mladenov said in a statement.
British Ambassador Simon Collis, meanwhile, said: "This latest example of violence against worshippers and journalists is further evidence of terrorists seeking to create division within Iraq."
Diplomats and analysts say the Shi'ite-led government's failure to address the grievances of Iraq's Sunni Arab minority -- which complains of political exclusion and abuses by security forces -- has driven the surge in unrest.
Violence worsened sharply after security forces stormed a Sunni Arab anti-government protest camp in northern Iraq on April 23, sparking clashes in which dozens died.
The authorities have made some concessions aimed at placating anti-government protesters and Sunnis in general, such as freeing prisoners and raising the salaries of Sunni anti-al-Qaeda fighters, but underlying issues remain.
And while security forces have carried out wide-ranging operations against militants for more than two months, they have yet to succeed in curbing the wave of attacks.
The latest violence takes this month's death toll to at least 160, and more than 4850 since the beginning of the year, according to AFP figures based on security and medical sources.
