A series of attacks in and around Baghdad, including a spate of car bombings, killed 17 people Monday as Iraqi forces pressed an assault against militant-held areas of Anbar province.

The latest bloodshed comes amid a surge in violence that left more than 1,000 people dead in January, the worst such figure in nearly six years, as security forces grapple with near-daily attacks and protracted battles with anti-government fighters.

Foreign leaders have urged the Shiite-led government to do more to reach out to the disaffected Sunni Arab minority in a bid to undercut support for militants.

But with parliamentary polls looming in less than three months, Prime Minister Nuri al-Maliki has taken a hard line.

Despite officials insisting operations against militants, including those affiliated with the Islamic State of Iraq and the Levant (ISIL) jihadist group, are having an impact, the bloodshed has continued unabated.

In and around the capital on Monday, five car bombs killed 13 people while authorities said they found the dumped bodies of three men and a woman. All were shot in the head and they appear to have been tortured.

Seven people were killed in two separate car bombs -- one of which was detonated by a suicide attacker -- in the town of Mahmudiyah, just south of the capital.

Six others were killed by vehicles rigged with explosives in the Baghdad neighbourhoods of Baladiyat, Hurriyah and Sadr City.

The killings in particular harken back to Iraq's brutal Sunni-Shiite sectarian war which raged from 2006 to 2007, when corpses were often found abandoned on the streets, with the victims' bodies bearing signs of torture.

North of Baghdad in restive Diyala province, separate attacks on security forces left two soldiers dead, while bombings also struck in ethnically-mixed Kirkuk province, wounding three people.

Violence has surged across Iraq in recent months, with more than 1,000 people killed nationwide in January, the highest such figure since April 2008, according to government data.

Shootings have largely targeted security forces and civil servants, while bombings have ripped through both Sunni and Shiite areas, striking markets, commercial streets, cafes and other areas where civilians congregate.

Security forces dismantle Ramadi bombs

No group immediately claimed responsibility for the latest attacks, but Sunni militant groups including ISIL have previously mounted coordinated bombing campaigns in the capital targeting civilians and security forces.

ISIL has also been involved in fighting security forces in Anbar province, a mostly-Sunni desert region bordering Syria where militants have for weeks held parts of Ramadi and all of Fallujah, which lies on Baghdad's doorstep.

On Monday, soldiers, police and pro-government armed tribesmen were pressing a joint operation against militant-held areas of Ramadi, with a security official and an AFP journalist reporting that pro-government forces held most of a crucial neighbourhood in the centre of the city.

Security forces were dismantling dozens of roadside bombs planted across the Malaab district, and were making slow progress in other parts of Ramadi without the advantage of aerial cover due to bad weather.

On Saturday, the defence ministry announced that bombardment and artillery had hit a neighbourhood of northern Fallujah, a rare military operation inside the city itself.

A security official told AFP that an assault on the city was imminent, but a journalist in Fallujah said the city was largely calm on Monday.

The army has largely stayed out of Fallujah, a short drive from Baghdad, fearing major incursions could ignite a protracted conflict with massive civilian casualties and damage to property.

US battles in the city, a bastion of militants following the 2003 US-led invasion, were among their bloodiest since the Vietnam War.

Along with ISIL, other militant groups and anti-government tribes have battled forces loyal to the central government.

The standoff has prompted more than 140,000 people to flee their homes, the UN refugee agency said, describing it as the worst displacement in Iraq since the peak of the 2006-2008 sectarian conflict.