At least 80 people were killed and 150 wounded today when a suicide truck bomb slammed into the central Baghdad district of Al-Sadriya, a security source said."A suicide truck bomb exploded near the Sadriya market, in central Baghdad on the east bank of the Tigris River. At least 80 people were killed and 150 wounded," the source said.The blast sent a long plume of thick grey smoke into the air just before dusk, a time when markets are usually crowded with shoppers out for food ahead of the night-time curfew.The bombing was the biggest attack this year and its casualty toll was second only to a series of Sadr City car bombings in November which killed more than 200 people.The Sadr City bombing was by far the largest attack in Iraq since the March 2003 US-led invasion of the country.Today's attack also came just two days after two suicide bombers killed 73 people and wounded 163 when they struck a market in the centre of Hilla, the predominantly Shiite capital of Babil province south of Baghdad.Prior to Saturday, the worst blast this year was in Baghdad on January 22, when 88 people were killed and 160 wounded as two car bombs slammed the Haraj second-hand market in a coordinated attack.