Iraq's largest Sunni political bloc announced it has pulled out from the government on Wednesday as a series of bomb attacks in Baghdad killed at least 79 people and wounded more than 100 others.

The deadliest bombing attack occurred in the afternoon when a suicide bomber drove an oil tanker rigged with explosives and blew it up at a busy petrol station in Baghdad's western neighborhood of Mansour.

At least 50 people were killed and some 60 others wounded in the deadly attack.

Earlier in the day, another deadly attack killed 20 people and wounded 40 others when a suicide bomber blew up an explosive-laden car near the al-Hurriyah Square in Karradah neighborhood.

Another car bomb attack killed three people and wounded five others when a car bomb went off at the Athoriyen popular marketplace in Doura district in southern Baghdad.

A fourth car bomb, parking in the Kendi thoroughfare in Baghdad's western neighborhood of Harthiyah, detonated and killed three civilians and wounded six others.

In addition, sporadic attacks in the violence-ridden capital killed at least four more people and wounded 12 others during the day.

A policeman was killed and seven others wounded in a roadside bomb explosion near the Ma'moun communications tower in Mansour neighborhood.

Separately, two off-duty policemen were shot dead when gunmen ambushed their car in the al-Saidiya neighborhood in southwest Baghdad.

In central Baghdad, gunmen shot dead Major General Maher Nuri with Baghdad's traffic police, while he was driving his car in the morning near the Nahdha area.

The Iraqi police said that five people were wounded when US aircraft bombarded targets in Baghdad's southern neighborhood of Zaafaraniyah. However, the US military did not confirm the incident.

Besides, the Iraqi police said that its patrols picked up 25 unidentified bodies from Baghdad's streets during the past 24 hours. The bullet-riddled bodies were bound and blindfolded with signs of torture, they said.

On the political front, Iraq's largest Sunni political bloc announced its withdrawal from Prime Minister Nuri al-Maliki's government over his failure to meet their demands, leaving Maliki's cabinet virtually with only Shiite and Kurds.

"The Iraqi Accordance Front announces its withdrawal from Nuri al-Maliki's government," Rafie al-Issawi, a key member of the front told reporters in Baghdad.

He said that the front's five Sunni ministers and Deputy Prime Minister Salam al-Zubaie would resign later in the day.

Last week, the Sunni Arab front gave Maliki's government a week of suspension to meet its demands which included a pardon for security detainees who were not charged with crimes, disband militias, give the front real participation in making decisions and a firm commitment to human rights.

"We have decided to withdraw from the government after it ignored our demands, especially, the pardon for security detainees not charged with crimes," Ibrahim Danoon, a front member told Xinhua.

Danoon held Maliki the responsibility for the possible deterioration of political process in the war-torn country.

Earlier, officials in Maliki's government said that the Sunni front was trying to blackmail Maliki.

The bloc's decision would not include withdrawal for its 44 lawmakers from the 275-seat parliament.

On Tuesday, Iraq's Kurdish president Jalal Talabani met top Sunni Arab politicians in a bid to save the Shiite-dominated government from possible collapse.

Talabani also warned of "negative consequences" on the country's national unity government if the Sunni ministers withdraw from the government.

The withdrawal of the Sunni bloc dealt another major blow to al-Maliki's government, which was facing a mounting political crisis.

In April, five cabinet ministers loyal to radical Shiite cleric Moqtada al-Sadr had also quit the government to protest al-Maliki's reluctance to announce a timetable for the withdrawal of the US forces from Iraq.

(Xinhua News Agency August 2, 2007)