BAGHDAD - Iraqi Prime Minister Haider al-Abadi directed military commanders on Sunday to face a court martial for abandoning their positions in Ramadi, as he pushed ahead with a campaign aimed at combating corruption and mismanagement.

Underlining the risks of the ambitious reform agenda, however, the head of parliament's integrity panel, which refers corruption cases to the courts, said his convoy had been targeted west of Baghdad on Saturday evening. Abadi is seeking to transform a system he says has encouraged graft and incompetence, depriving Iraqis of basic services while undermining government forces in the battle against Islamic State militants.

Critics say sectarian splits and corruption have also weakened the military, allowing the insurgents to control large swathes of territory in the country's north and west over the past year. Ramadi, the capital of western Anbar province, fell to the group in May, dampening Baghdad's hopes of quickly routing them following earlier victories in eastern provinces. The army's collapse a year earlier in the face of Islamic State's takeover of the northern city of Mosul left the Baghdad government dependent on militias, many funded and assisted by neighbouring Iran, to defend the capital and recapture lost ground.

Baghdad-based analyst Jasim al-Bahadli said Abadi was wise to focus his reforms on the security forces.

"Abadi's decision to refer military commanders to trial is a clear attempt to send a strong message to all other army officers that he will show zero tolerance with any future retreat in the fight against Daesh (Islamic State)," said Bahadli, a former army general and an expert on Shia armed groups. In a sign of the opposition to Abadi's plans, parliament integrity chief Talal al-Zobaie said his motorcade was attacked on Saturday evening near Abu Ghraib, 24 km (15 miles) west of Baghdad.

Zobaie said a bomb hit a vehicle carrying his bodyguards. Gunmen then fired on the convoy, killing a bodyguard and wounding three others.

"It's understood I was targeted because I'm going after corrupt people," he told Reuters. "This vicious attack will never make me relent in pursuing my job in going after corruption cases."

A separate bomb attack on Sunday killed at least four people and wounded 14 others near a crowded market in the mainly Shia district of Jisr Diyala, southeast of Baghdad.

There was no immediate claim of responsibility, but Islamic State regularly targets areas of the capital populated by Shias, whom it considers heretics.

In a statement circulated online by supporters, the group claimed an attack on Saturday evening in the district of Habibiya that killed at least 15 people.

Meanwhile, an Iraqi parliamentary panel called on Sunday for dozens of security and political officials, including former Prime Minister Nuri al-Maliki, to be referred to court in connection with the fall of the northern city of Mosul to Islamic State.

The indictment of Maliki, who remains a powerful figure in Iraq's complex political landscape, and other senior officials comes a week after Prime Minister Haider al-Abadi launched a sweeping campaign to combat corruption and mismanagement that he argued had made the country nearly impossible to govern.

In the panel's report, seen by Reuters and confirmed as accurate by three of its members, the committee also placed responsibility for the June 2014 defeat with former Mosul Governor Atheel al-Nujaifi, former acting defence minister Sadoun al-Dulaimi, former army chief General Babakir Zebari and Lieutenant General Mahdi al-Gharrawi, former operational commander of Nineveh province, of which Mosul is the capital.

Others accused include Nineveh police commander Major General Khalid Hamdani and former Deputy Interior Minister Adnan al-Assadi.

There has been no official accounting of how Mosul was lost, and who gave the order to abandon the fight. The fall of the city - Iraq's second-largest - was a turning point in Islamic State's seizure of large swathes of the country's north and west in a sweep across the Syrian border last year.

An investigation by Reuters in October showed how troop shortages in Mosul and infighting among top officers and Iraqi political leaders played into Islamic State's hands and fuelled panic that led to the city's abandonment. Maliki has accused unnamed countries, commanders and rival politicians of plotting the fall of Mosul.

The parliamentary report was approved by 16 of the panel's 24 members, lawmaker Muhsin Sadoun said.

Panel member Mohammed al-Karabouli said parliament would vote on the report's findings on Monday and then refer it to Abadi, the prosecutor general and the integrity commission.

"No one is above the law and accountability to the people," said Parliament Speaker Saleem al-Jabouri in a statement upon receiving the report. "The judiciary will punish perpetrators and delinquents."