At least 20 people were killed and 80 wounded Thursday evening in a central Baghdad blast, independent Voices of Iraq reported citing a police source, according to dpa. A huge explosion, believed to be a car bomb, occurred in the predominantly Shiite central neighbourhood of Karrada, causing severe damage to cars and stores in the area, the source added. Other witnesses said the blast resulted from a building rigged with explosives and that the building collapsed, Voices of Iraq said. Karrada has repeatedly seen attacks. On Monday, three car bombs went off consecutively in the district, killing at least 12 people and wounding 20. In other developments Thursday, Iraq's Vice President called on officials in charge of the Baghdad security plan to explain the killing of 50 Iraqis celebrating the victory of their national football team in Baghdad, Voices of Iraq reported. Two car bombs exploded in the Iraqi capital Baghdad's Mansour neighbourhood Wednesday evening killing 50 civilians and injuring 153 who were in the streets celebrating Iraq's national football team reaching the finals of the Asian Nations Cup. Tareq al-Hashemi said the killings were the result of a "security breach", adding: "Those in charge of the Baghdad security plan should provide prompt and clear explanation for what happened. Why are they silent on these crimes as if the matter does not concern them?" An Iraqi police source meanwhile said five Iraqi policeman from the emergency police forces were killed and two wounded when an explosive charge targeted their patrol in southern Hillah, 100 kilometres south of Baghdad. Six US soldiers have been killed in an operation conducted by joint Iraqi-US forces in the northern Baghdad neighbourhood of Husainiya, Voices of Iraq reported, citing a spokesman for the Fardh al-Qanoun - Law Enforcement - security plan. The spokesman added the US forces had lifted the siege it had imposed on Husainiya. Fardh al-Qanoun security operation commander Aboud Qanbar told reporters in Baghdad that "the reasons behind the security crackdown in Husainiya were the militants' acts of closing roads, planting explosive charges and preventing security forces from entering the area." Joint US-Iraqi forces raided the predominantly-Shiite district of Husainiya in north-eastern Baghdad late Friday. While the US military said Saturday that six militants had been killed during an airstrike on the Shiite stronghold, local residents said that 18 civilians had been killed in the attack and that three houses had been destroyed. Hundreds of angry Husainiya residents have been demonstrating in the streets this week protesting against the siege imposed on the district following the raid. Other protests in Baghdad's Shiite Sadr City also broke out calling for the lifting of the security cordon on Husainiya. Also Thursday, US-led coalition forces detained 36 terrorist suspects during operations in central and northern Iraq targeting the al-Qaeda in Iraq network, the US military in Iraq reported.