At least 89 people were killed in bomb and gun attacks in Iraq on Monday after 20 died in blasts the previous day in a coordinated surge of violence against mostly Shi'ite Muslim targets.
The bloodshed coincided with an intensifying of the conflict in neighbouring Syria.
As well as the dozens of deaths at least 223 people were wounded in bomb attacks in Shi'ite areas of Baghdad, the Shi'ite town of Taji to the north, the mixed northern city of Kirkuk and elsewhere, hospital and police sources said, making it one of Iraq's bloodiest days in weeks.
No group has claimed responsibility for the latest wave of assaults but a senior Iraqi security official blamed the local wing of al Qaeda, made up of Sunni Muslim militants hostile to the Shi'ite-led government, which is friendly with Iran.
"Recent attacks are a clear message that al Qaeda in Iraq is determined to spark a bloody sectarian war," the official said, asking not to be named.
"With what's going on in Syria, these attacks should be taken seriously as a potential threat to our country. Al Qaeda is trying to push Iraq to the verge of Shi'ite-Sunni war," he said. "They want things to be as bad as in Syria."
The last two days of bombings and shootings shattered a two-week lull in violence in the run-up to the Muslim holy fasting month of Ramadan, which started in Iraq on Saturday.
Sectarian slaughter peaked in 2006-2007 but deadly attacks have persisted while political tensions among Iraq's main Shi'ite, Sunni and Kurdish factions have mounted since U.S. troops left the country in December.
TRAIL OF DESTRUCTION
In Taji, 20 km (12 miles) north of Baghdad, six explosions, including a car bomb, went off near a housing complex. A seventh blast there caused carnage among police who had arrived at the scene of the earlier ones. In all 32 people were killed, including 14 police, and 48 wounded, 10 of them police.
Two car bombs struck near a government building in Sadr City, a vast, poor Shi'ite swathe of Baghdad, and in the mainly Shi'ite area of Hussainiya on the outskirts of the capital, killing a total of 11 people and wounding 73, police said.
In Kirkuk, five car bombs killed six people and wounded 17, while explosions and gun attacks on security checkpoints around the restive province of Diyala killed six people, including four soldiers and policemen, and wounded 30, police sources said.
Two car bombs parked near a military checkpoint killed five people and wounded 22 in the town of Khan Bani Saad, 30 km (20 miles) northeast of Baghdad, police sources said. Gunmen killed four soldiers and wounded five in an attack on a checkpoint in the town of Udhaim, 90 km north of the capital, they said.
The orchestrated spate of attacks followed car bombs on Sunday in two towns south of Baghdad and in the Shi'ite shrine city of Najaf that killed 20 people and wounded 80.
Last month was one of the bloodiest since the U.S. withdrawal, with at least 237 people killed and 603 wounded.
Iraq, whose huge desert province of Anbar, a Sunni heartland, borders Syria, is nervous about the impact of the conflict raging in its neighbour, scene of a Sunni-led revolt against President Bashar al-Assad's Alawite-dominated rule.