BAGHDAD — Car bombs struck Shiite neighborhoods of the Iraqi capital and a northern city on Thursday, killing 16 people, while gunmen in Baghdad shot dead the brother of a Sunni lawmaker, officials said.

The attacks followed a wave of bombings Wednesday that also struck in mainly in Shiite neighborhoods, killing 33 people and raising concerns over a return to the sectarian bloodshed in Iraq.

Baghdad police said the first of Thursday’s bombings hit a bus and taxi stop during the morning rush hour in the city’s eastern Sadr City neighborhood. Nine people were killed, including a 7-year old child, and 16 were wounded in that attack, two officers said.

Another car bomb hit a small market at a taxi stop in Baghdad’s eastern suburb of Kamaliya, killing three civilians and wounding 14 others there, the officers said.

And in the capital’s northern Chikok district, two civilians were killed and 10 were wounded when a car bomb missed a police patrol that was passing through, two other police officers said.

In the northern city of Mosul, a suicide attacker rammed his car into an army check point, killing two soldiers and wounding three others, another police officer said. The attack came just after a car bombing in another area of Mosul wounded two civilians, he said. Mosul is located 360 kilometers (225 miles) northwest of Baghdad.

In Baghdad’s southwestern neighborhood of Baiyaa, drive-by gunmen shot and killed a brother of a Sunni lawmaker and wounded two of his guards, two police officials said.

Four medical officials in a nearby hospital confirmed the causality figures. All officials spoke on condition of anonymity because they were not authorized to talk to the media.

The spike in violence comes amid growing tensions between the Shiite-led government and Iraq’s Sunni minority over what they consider second-class treatment. A bloody government crackdown on militants last month in a protest camp in the country’s north fueled the latest tensions.

Iraq’s embattled Shiite Prime Minister Nouri al-Maliki on Thursday blamed sectarian tensions for the latest attacks.

“We have to know that today’s bloodshed is the result of sectarian hatred and also the result of a stirring up of these sectarian tensions,” al-Maliki said during a government-organized conference about atrocities committed under dictator Saddam Hussein.

Incitement could be coming from inside or outside the country, al-Maliki added.

No one has claimed responsibility for Wednesday’s and Thursday’s attacks, but car and suicide bombings are a hallmark of al-Qaida’s Iraq branch.

The spike in attacks, after a general decrease in violence, has raised fears of a return to the sectarian bloodshed that pushed Iraq to the brink of civil war in 2006-2007. Shiite militias have so far been largely restrained in their reactions to such bombings.

Earlier on HuffPost:

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  • Iraqis chant anti-government slogans as others wave representations of older national flags at an anti-government rally in Fallujah, Iraq, Friday, May 3, 2013. A bomb attack outside the al-Ghofran mosque in a primarily Sunni area of Rashidiya on Friday killed several worshippers as Sunnis continued to hold demonstrations in Iraq to protest what they say is second-class treatment by the Shiite-led government. (AP Photo/Bilal Fawzi)

  • Sunni protesters wave Islamist flags while others chant slogans at an anti-government rally in Fallujah, Iraq, Friday, May 3, 2013. A bomb attack outside the al-Ghofran mosque in a primarily Sunni area of Rashidiya on Friday killed seven worshippers as Sunnis continued to hold demonstrations in Iraq to protest what they say is second-class treatment by the Shiite-led government. (AP Photo/Bilal Fawzi)

  • Iraq’s national flag flies as followers of radical Shiite cleric Muqtada al-Sadr attend Friday prayers in the Sadr City neighborhood in Baghdad, Iraq, Friday, May 3, 2013. The United Nations mission to Iraq says more people were killed in violent attacks across the country in April than in any other month since June 2008. The U.N. figures released on Thursday, May 2, 2013 underscore concerns that security is quickly deteriorating in Iraq, where violence spiked in the last part of April. (AP Photo/Karim Kadim)

  • A member of the Iraqi security forces monitor a checkpoint using a fake explosive detecting device in the al-Jadriyah district of Baghdad on May 3, 2013. A British businessman was sentenced to 10 years in jail for selling fake bomb detectors to the Iraqi government and other countries, by a judge who told him he had blood on his hands. AFP PHOTO / ALI AL-SAADI (Photo credit should read ALI AL-SAADI/AFP/Getty Images)

  • FILE – In this Tuesday, April 23, 2013 file photo, the body of a gunman killed during clashes with Iraqi security forces lies on the ground in Hawija, 150 miles (240 kilometers) north of Baghdad, Iraq. Iraqi Deputy Prime Minister Saleh al-Mutlaq the head of a committee established to investigate deadly clashes that erupted at a Sunni protest camp in Iraq last week says excessive force was used by security forces. (AP Photo, File)

  • in this Tuesday, April 23, 2013 file photo, Iraqi army soldiers stage on the outskirts of Hawija, 150 miles (240 kilometers) north of Baghdad, Iraq. Iraqi Deputy Prime Minister Saleh al-Mutlaq the head of a committee established to investigate deadly clashes that erupted at a Sunni protest camp in Iraq last week says excessive force was used by security forces. (AP Photo, File)

  • In this Tuesday, April 23, 2013 file photo, AK-47s seized by Iraqi security forces are seen in Hawija, 150 miles (240 kilometers) north of Baghdad, Iraq. A shadowy militant group linked to the highest-ranking member of Saddam Hussein’s regime still at large could be among the beneficiaries of the unrest that erupted this week in Iraq and is posing perhaps the gravest challenge for Iraq’s stability since U.S. troops left. The Army of the Men of the Naqshabandi Order, which takes its name from the mystical Sufi sect, has long been active in the restless northern lands where much of the violence occurred and boasts itself that it was behind several attacks in recent days.(AP Photo, File)

  • Iraqi anti-government gunmen from Sunni tribes in the western Anbar province march during a protest in Ramadi, west of Baghdad, on April 26, 2013. The United Nations warned that Iraq is at a ‘crossroads’ and appealed for restraint, as a bloody four-day wave of violence killed 195 people. The violence is the deadliest so far linked to demonstrations that broke out in Sunni areas of the Shiite-majority country more than four months ago, raising fears of a return to all-out sectarian conflict. (AZHAR SHALLAL/AFP/Getty Images)

  • Iraqi anti-government gunmen from Sunni tribes in the western Anbar province march during a protest in Ramadi, west of Baghdad, on April 26, 2013. The United Nations warned that Iraq is at a ‘crossroads’ and appealed for restraint, as a bloody four-day wave of violence killed 195 people. The violence is the deadliest so far linked to demonstrations that broke out in Sunni areas of the Shiite-majority country more than four months ago, raising fears of a return to all-out sectarian conflict. ( AZHAR SHALLAL/AFP/Getty Images)

  • An Iraqi anti-government gunman from Sunni tribes in the western Anbar province takes part in a protest in Ramadi, west of Baghdad, on April 26, 2013. The United Nations warned that Iraq is at a ‘crossroads’ and appealed for restraint, as a bloody four-day wave of violence killed 195 people. The violence is the deadliest so far linked to demonstrations that broke out in Sunni areas of the Shiite-majority country more than four months ago, raising fears of a return to all-out sectarian conflict. (AZHAR SHALLAL/AFP/Getty Images)