BAGHDAD - Iraq began on Monday a three-day national mourning for victims of Sunday's car bombing attacks in the capital city of Baghdad, as the death toll rises to 166.

An Interior Ministry source said at least 165 people were killed and 225 others wounded in a suicide bomb attack in Karrada-Dakhil district in southern Baghdad. Another one was killed in a separate car bombing in a market in northeastern Baghdad.

The Karrada-Dakhil bombing is the bloodiest attack this year in the country, where the army is fighting Islamic State militants.

The busy commercial district in southern Baghdad was hit by a car bomb at about 1:00 a.m. local time (2200GMT) on Sunday when a suicide bomber detonated his explosive-laden pickup truck outside a shopping center.

The three-floor building was destroyed, when many people were inside. Many of the victims were women and children, the source said. Rescuers said the explosion and the following huge fire killed all members in some families.

Prime Minister Haider al-Abadi announced three days of national mourning for the victims after he visited the blast site on Sunday. His convoy was attacked by dozens of angry residents who accused the government of failing to protect its people.

Local resident Mohammed Musa said: "now we demand a solution from the government, because since 2003 to 2016 we have been uncomfortable, we are in a difficult situation. And those people, all of them lost their money, property and lives and other things. Everything is gone."

As the commander-in-chief of Iraqi forces, Abadi ordered an intensification of security measures on the entrances of Baghdad and in other Iraqi provinces.

Sunday's powerful blast set fire to the shopping center and four nearby buildings while many shops and stalls were charred and destroyed, as well as dozens of civilian vehicles at the scene. The fire was put out in the afternoon and rescue operations continued till night.

Dozens of rescue workers, firefighters and civilians were removing debris and burned wreckage from dawn to the evening, looking for survivors and bodies.