Apparently coordinated bombings mainly targeting Shiite areas of Baghdad killed 23 people Thursday, after Iraqi Prime Minister Nuri al-Maliki vowed to press a campaign against militants to stem spiralling violence.

Security forces have carried out major operations against militants in recent weeks, but the relentless violence has raised fears Iraq could slip back into the all-out sectarian bloodshed of 2006-2007.

Overall, six car bombings and a roadside explosion struck six different areas of the capital during morning rush hour -- five of them Shiite-majority and a sixth mixed -- also wounding more than 70 people.

In the single deadliest attack, a car bomb exploded at a bus station in the Kadhimiyah area of north Baghdad, killing seven people and wounding 24.

Another car bomb blew up in Baladiyat near an office of Al-Ahad television, which is affiliated with Asaib Ahl al-Haq, a Shiite militant group that split from powerful Shiite cleric Moqtada al-Sadr's Mahdi Army.

"I was parking my car and, all of a sudden, the bomb went off," said 38-year-old taxi driver Haitham Khalaf, whose vehicle's windshield was badly damaged by a blast in central Baghdad's Allawi neighbourhood.

"I was slipping in and out of consciousness, I was so confused. I only heard the explosion, and then I fell. I couldn't feel anything. I was in shock, it was such a big explosion.

"I am thankful to God that I am safe," said Khalaf, who was not wounded in the attack, standing close to multiple military vehicles that blocked off entry to the street where the bombing took place.

"We only pray to God that this (violence) will be over."

Nearby vehicles and shops were badly damaged by the Allawi blast, as a crane picked up debris and emergency workers cleared the scene.

No group immediately claimed responsibility for the attacks, but Sunni militants including those linked to Al-Qaeda frequently target members of Iraq's Shiite Muslim majority, whom they consider apostates.

The violence came a day after attacks including a blast at a cafe north of the capital killed 17 people.

Another wave of attacks claimed by an Al-Qaeda front group, the Islamic State of Iraq and the Levant, struck areas across Iraq on Saturday, killing 74 people, among them 47 in Baghdad.

On Wednesday, Maliki said security forces would continue large-scale efforts to hunt militants.

"The operation that we started in chasing terrorists, and those who stand behind them, will continue until we protect our people," Maliki said.

He said more than 800 alleged militants had been detained and dozens of others killed, and that security forces had destroyed militant infrastructure used to make car bombs and seized a large amounts of weapons and explosives.

The premier did not, however, specify when the arrests were made, where the operations took place or who had carried them out.

Security forces have for weeks been carrying out wide-ranging operations in multiple provinces including Baghdad, after brazen July assaults on two major prisons, claimed by the Islamic state of Iraq and the Levant.

Hundreds of inmates were freed in the well-coordinated attacks, among them some said to be senior militants, raising fears the escapes will bolster armed groups in Iraq.

But despite the regular announcements of the killing or capture of fighters in recent weeks, attacks still plague daily life.

Violence has markedly increased this year, especially since an April 23 security operation at a Sunni Arab anti-government protest site that sparked clashes in which dozens died.

Analysts say Sunni anger is the main cause of the spike in violence this year.

Attacks have killed more than 3,460 people in Iraq since the beginning of 2013, according to figures compiled by AFP -- an average over 15 per day.

And Iraqi government figures showed that nearly 1,000 people were killed in violence in July, making it the deadliest month for the country since 2008.