Attacks in the Baghdad area and northern Iraq killed 58 people on Monday, the latest in a wave of violence that has raised fears of a return to sectarian conflict in the country.

The unrest, including bombings in Baghdad that mainly targeted Shiite areas, comes at a time of heightened tensions in Iraq, with the Sunni minority accusing the Shiite-led government of marginalising and targeting their community.

With the new attacks, nearly 1,000 people have been killed in Iraq in less than two months -- a bloody wave of unrest Iraqi authorities have so far failed to stem.

No group immediately claimed responsibility for the latest attacks, but Sunni militants linked to Al-Qaeda often set off coordinated explosions, in particular targeting Shiites whom they regard as apostates, in a bid to foster tensions and undermine confidence in the security forces.

More than a dozen bombings in and around Baghdad killed at least 55 people and wounded 187, security and medical officials said.

Two of the blasts, both involving vehicles rigged with explosives, went off near used car dealerships in Habibiyah, destroying dozens of cars as Iraq's national football team were playing Liberia in a friendly at Shaab stadium a short distance away.

"Guards are here, and a car explodes here," screamed Fadhel Hanoun, a used car dealer who lamented that not only had people died, but many had lost their savings, locked up in cars they had hoped to sell.

"How can we understand this?" he said, adding: "This is a failed state."

Another man walked past, crying and shouting, "You must know, this was an organised operation."

"Checkpoints, they do not actually check the cars entering here," he said, alluding to the multiple searches vehicles had to pass through to get to the dealerships.

Baghdad has been hit by a number of bombings, often in Shiite areas, so far this month, in which dozens of people have died.

Elsewhere, shootings in the disputed province of Kirkuk killed an anti-Al-Qaeda militiaman and a private generator operator, while a roadside bomb in the main northern city of Mosul left a police colonel dead.

Iraq's autonomous Kurdish region wants to incorporate oil-rich Kirkuk over the federal government's strong objections -- a dispute diplomats and officials say is a major threat to the country's long-term stability.

The areas of north Iraq where the attacks occurred are home to substantial populations of Sunni Arabs, the community that has for months held demonstrations against alleged government targeting and discrimination.

While the government has made some concessions aimed at placating protesters and Iraqi Sunnis in general, such as freeing prisoners and raising the salaries of Sunni anti-Al-Qaeda fighters, underlying issues have yet to be addressed.

And an April 23 security forces raid on a protest site that sparked clashes in which dozens died sent tensions soaring higher still.

Analysts say government policies that have disenfranchised Iraqi Sunnis, coupled with Shiite-led authorities' refusal to make any major concessions to the protesters, have given militant groups fuel and room to manoeuvre among the disillusioned community.

With the latest attacks, more than 500 people have been killed in May, making in the deadliest month in at least a year.

Prime Minister Nuri al-Maliki last week ordered a shake-up of top security officers in the country's provincial security commands and division-level leadership.

One of those changes was to sack the head of the Baghdad Operations Command, which is responsible for security in the capital.

The unrest also comes amid myriad political rows and fears that civil war in neighbouring Syria could spill over into Iraq and plunge the country further into crisis.

A massive operation by Iraqi security forces against Sunni militants in the country's western desert, which included the deployment of troops on the border with Syria, entered its third day on Monday.

Violence in Iraq has decreased from its peak at the height of Iraq's sectarian conflict in 2006 and 2007, but attacks remain common, killing at least 220 people each month so far this year.