A car bomb apparently targeting the leader of Iraq's largest Sunni political party wounded four people northeast of Baghdad on Thursday, police said. The politician escaped unharmed.

Police said the car, parked near a restaurant in the city of Baqouba, exploded two minutes after a convoy passed by with the leader of the Iraqi Islamic Party, Osama al-Tikriti, and other officials. Four civilian bystanders were wounded in the blast, which destroyed a number of shops along Baqouba's main street, said police Capt. Ghalib al-Karkhi.

The city, 35 miles (60 kilometers) northeast of Baghdad, was once a stronghold for insurgents, but violence has eased there, as it has across Iraq, overall. In cities like Baghdad and Mosul in the north, however, bombings and other violence have persisted.

Iraqi Prime Minister Nouri al-Maliki, who has used the security improvements in his campaign for January's national elections, is under criticism for security lapses that aided bombers who struck government ministries in Baghdad in August.

On Thursday, he met with a group of ambassadors to press his case that those who plotted the attacks are based in neighboring Syria. The Aug. 19 truck bombings outside the foreign and finance ministries killed about 100 people.

Iraq, which has blamed an alliance between Al Qaeda in Iraq and Saddam Hussein's outlawed Baath Party for the attacks, wants Syria to hand over several suspects it says are based there.

Syria is home to a number of Iraqis who were mid-ranking and senior members of Saddam's Baath Party, and Iraqi officials say Damascus allows them to live and engage in political activity in Syria.

Syria, which has demanded to see proof for Iraq's claims, accuses al-Maliki's government of seeking to exploit the attacks to press demands for the handover of Iraqi opposition figures living in Damascus.