BAGHDAD, Dec. 8 -- A total of 51 people were killed and 191 others wounded in violent attacks across Iraq on Sunday, mostly in the capital Baghdad, police said.

Five people were killed and 18 others injured when a car bomb exploded Sunday evening in the Aalam neighborhood of southwestern Baghdad, a police source told Xinhua.

Three people were killed and 16 others wounded when a car bomb went off in a popular market in the Jamela area in eastern Baghdad, the source said, adding that one civilian was killed and five others were injured when another car bomb exploded in the Talbiya area of eastern Baghdad.

Earlier in the day, a total of 13 bombing attacks predominantly ripped through Shiite districts in Baghdad, killing at least 38 people and wounding some 146 others.

In Iraq's eastern province of Diyala, a civilian was killed and six were wounded in a car bomb explosion near a restaurant in the town of Jadidat al-Shat, some 30 km northwest of the provincial capital city of Baquba, which is about 65 km northeast of Baghdad, a provincial police source said.

Near Baquba, gunmen shot dead Ahmed al-Khafaji, head of the provincial media office for the leading Shiite party of the Islamic Supreme Council of Iraq (ISCI), headed by Shiite cleric Ammar al-Hakim, the source said.

Also in Diyala, two more people were shot dead by gunmen in two incidents near Baquba during the day, the source added.

No group has so far claimed responsibility for the deadly attacks, but the al-Qaida front in Iraq, in most cases, were responsible for suicide bombings in the country.

Sunday's attacks came amid escalation of sectarian tension between the Sunni and Shiite communities, which has been at its highest level since the U.S. troops pulled out from the country at the end of 2011.

Iraq is witnessing its worst eruption of violence in recent years. According to the UN Assistance Mission for Iraq, 8,109 Iraqis were killed in the country from January to November 2013.